From 10e15b91340f297212bd24de5b15f60d30b439ad Mon Sep 17 00:00:00 2001
From: cm-ayf <cm.ayf2734@gmail.com>
Date: Mon, 15 Jan 2024 15:31:41 +0900
Subject: [PATCH] add serializer

---
 src/fixture.rs         | 547 +++++++++++++++++++++++++++++++++++++++++
 src/lib.rs             |   4 +
 src/parser/mod.rs      |   2 +-
 src/parser/test.rs     | 547 +----------------------------------------
 src/serializer/mod.rs  | 318 ++++++++++++++++++++++++
 src/serializer/test.rs |   9 +
 6 files changed, 882 insertions(+), 545 deletions(-)
 create mode 100644 src/fixture.rs
 create mode 100644 src/serializer/mod.rs
 create mode 100644 src/serializer/test.rs

diff --git a/src/fixture.rs b/src/fixture.rs
new file mode 100644
index 0000000..630d383
--- /dev/null
+++ b/src/fixture.rs
@@ -0,0 +1,547 @@
+use crate::fullcontext_label::{
+    AccentPhraseCurrent, AccentPhrasePrevNext, BreathGroupCurrent, BreathGroupPrevNext, Label,
+    Mora, Phoneme, Utterance, Word,
+};
+
+pub fn fixtures() -> [(&'static str, Label); 11] {
+    [
+        (
+            "xx^xx-sil+k=o/A:xx+xx+xx/B:xx-xx_xx/C:xx_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:xx_xx#xx_xx@xx_xx|xx_xx/G:5_5%0_xx_xx/H:xx_xx/I:xx-xx@xx+xx&xx-xx|xx+xx/J:1_5/K:1+1-5",
+            Label {
+                phoneme: Phoneme {
+                    p2: None,
+                    p1: None,
+                    c: Some("sil".to_string()),
+                    n1: Some("k".to_string()),
+                    n2: Some("o".to_string()),
+                },
+                mora: None,
+                word_prev: None,
+                word_curr: None,
+                word_next: None,
+                accent_phrase_prev: None,
+                accent_phrase_curr: None,
+                accent_phrase_next: Some(AccentPhrasePrevNext {
+                    mora_count: 5,
+                    accent_position: 5,
+                    is_interrogative: false,
+                    is_pause_insertion: None
+                }),
+                breath_group_prev: None,
+                breath_group_curr: None,
+                breath_group_next: Some(BreathGroupPrevNext {
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                }),
+                utterance: Utterance {
+                    breath_group_count: 1,
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                },
+            },
+        ),
+        (
+            "xx^sil-k+o=N/A:-4+1+5/B:xx-xx_xx/C:09_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:5_5#0_xx@1_1|1_5/G:xx_xx%xx_xx_xx/H:xx_xx/I:1-5@1+1&1-1|1+5/J:xx_xx/K:1+1-5",
+            Label {
+                phoneme: Phoneme {
+                    p2: None,
+                    p1: Some("sil".to_string()),
+                    c: Some("k".to_string()),
+                    n1: Some("o".to_string()),
+                    n2: Some("N".to_string()),
+                },
+                mora: Some(Mora {
+                    relative_accent_position: -4,
+                    position_forward: 1,
+                    position_backward: 5,
+                }),
+                word_prev: None,
+                word_curr: Some(Word {
+                    pos: Some(9),
+                    ctype: None,
+                    cform: None,
+                }),
+                word_next: None,
+                accent_phrase_prev: None,
+                accent_phrase_curr: Some(AccentPhraseCurrent {
+                    mora_count: 5,
+                    accent_position: 5,
+                    is_interrogative: false,
+                    accent_phrase_position_forward: 1,
+                    accent_phrase_position_backward: 1,
+                    mora_position_forward: 1,
+                    mora_position_backward: 5,
+                }),
+                accent_phrase_next: None,
+                breath_group_prev: None,
+                breath_group_curr: Some(BreathGroupCurrent {
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                    breath_group_position_forward: 1,
+                    breath_group_position_backward: 1,
+                    accent_phrase_position_forward: 1,
+                    accent_phrase_position_backward: 1,
+                    mora_position_forward: 1,
+                    mora_position_backward: 5,
+                }),
+                breath_group_next: None,
+                utterance: Utterance {
+                    breath_group_count: 1,
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                },
+            },
+        ),
+        (
+            "sil^k-o+N=n/A:-4+1+5/B:xx-xx_xx/C:09_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:5_5#0_xx@1_1|1_5/G:xx_xx%xx_xx_xx/H:xx_xx/I:1-5@1+1&1-1|1+5/J:xx_xx/K:1+1-5",
+            Label {
+                phoneme: Phoneme {
+                    p2: Some("sil".to_string()),
+                    p1: Some("k".to_string()),
+                    c: Some("o".to_string()),
+                    n1: Some("N".to_string()),
+                    n2: Some("n".to_string()),
+                },
+                mora: Some(Mora {
+                    relative_accent_position: -4,
+                    position_forward: 1,
+                    position_backward: 5,
+                }),
+                word_prev: None,
+                word_curr: Some(Word {
+                    pos: Some(9),
+                    ctype: None,
+                    cform: None,
+                }),
+                word_next: None,
+                accent_phrase_prev: None,
+                accent_phrase_curr: Some(AccentPhraseCurrent {
+                    mora_count: 5,
+                    accent_position: 5,
+                    is_interrogative: false,
+                    accent_phrase_position_forward: 1,
+                    accent_phrase_position_backward: 1,
+                    mora_position_forward: 1,
+                    mora_position_backward: 5,
+                }),
+                accent_phrase_next: None,
+                breath_group_prev: None,
+                breath_group_curr: Some(BreathGroupCurrent {
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                    breath_group_position_forward: 1,
+                    breath_group_position_backward: 1,
+                    accent_phrase_position_forward: 1,
+                    accent_phrase_position_backward: 1,
+                    mora_position_forward: 1,
+                    mora_position_backward: 5,
+                }),
+                breath_group_next: None,
+                utterance: Utterance {
+                    breath_group_count: 1,
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                },
+            },
+        ),
+        (
+            "k^o-N+n=i/A:-3+2+4/B:xx-xx_xx/C:09_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:5_5#0_xx@1_1|1_5/G:xx_xx%xx_xx_xx/H:xx_xx/I:1-5@1+1&1-1|1+5/J:xx_xx/K:1+1-5",
+            Label {
+                phoneme: Phoneme {
+                    p2: Some("k".to_string()),
+                    p1: Some("o".to_string()),
+                    c: Some("N".to_string()),
+                    n1: Some("n".to_string()),
+                    n2: Some("i".to_string()),
+                },
+                mora: Some(Mora {
+                    relative_accent_position: -3,
+                    position_forward: 2,
+                    position_backward: 4,
+                }),
+                word_prev: None,
+                word_curr: Some(Word {
+                    pos: Some(9),
+                    ctype: None,
+                    cform: None,
+                }),
+                word_next: None,
+                accent_phrase_prev: None,
+                accent_phrase_curr: Some(AccentPhraseCurrent {
+                    mora_count: 5,
+                    accent_position: 5,
+                    is_interrogative: false,
+                    accent_phrase_position_forward: 1,
+                    accent_phrase_position_backward: 1,
+                    mora_position_forward: 1,
+                    mora_position_backward: 5,
+                }),
+                accent_phrase_next: None,
+                breath_group_prev: None,
+                breath_group_curr: Some(BreathGroupCurrent {
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                    breath_group_position_forward: 1,
+                    breath_group_position_backward: 1,
+                    accent_phrase_position_forward: 1,
+                    accent_phrase_position_backward: 1,
+                    mora_position_forward: 1,
+                    mora_position_backward: 5,
+                }),
+                breath_group_next: None,
+                utterance: Utterance {
+                    breath_group_count: 1,
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                },
+            },
+        ),
+        (
+            "o^N-n+i=ch/A:-2+3+3/B:xx-xx_xx/C:09_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:5_5#0_xx@1_1|1_5/G:xx_xx%xx_xx_xx/H:xx_xx/I:1-5@1+1&1-1|1+5/J:xx_xx/K:1+1-5",
+            Label {
+                phoneme: Phoneme {
+                    p2: Some("o".to_string()),
+                    p1: Some("N".to_string()),
+                    c: Some("n".to_string()),
+                    n1: Some("i".to_string()),
+                    n2: Some("ch".to_string()),
+                },
+                mora: Some(Mora {
+                    relative_accent_position: -2,
+                    position_forward: 3,
+                    position_backward: 3,
+                }),
+                word_prev: None,
+                word_curr: Some(Word {
+                    pos: Some(9),
+                    ctype: None,
+                    cform: None,
+                }),
+                word_next: None,
+                accent_phrase_prev: None,
+                accent_phrase_curr: Some(AccentPhraseCurrent {
+                    mora_count: 5,
+                    accent_position: 5,
+                    is_interrogative: false,
+                    accent_phrase_position_forward: 1,
+                    accent_phrase_position_backward: 1,
+                    mora_position_forward: 1,
+                    mora_position_backward: 5,
+                }),
+                accent_phrase_next: None,
+                breath_group_prev: None,
+                breath_group_curr: Some(BreathGroupCurrent {
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                    breath_group_position_forward: 1,
+                    breath_group_position_backward: 1,
+                    accent_phrase_position_forward: 1,
+                    accent_phrase_position_backward: 1,
+                    mora_position_forward: 1,
+                    mora_position_backward: 5,
+                }),
+                breath_group_next: None,
+                utterance: Utterance {
+                    breath_group_count: 1,
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                },
+            },
+        ),
+        (
+            "N^n-i+ch=i/A:-2+3+3/B:xx-xx_xx/C:09_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:5_5#0_xx@1_1|1_5/G:xx_xx%xx_xx_xx/H:xx_xx/I:1-5@1+1&1-1|1+5/J:xx_xx/K:1+1-5",
+            Label {
+                phoneme: Phoneme {
+                    p2: Some("N".to_string()),
+                    p1: Some("n".to_string()),
+                    c: Some("i".to_string()),
+                    n1: Some("ch".to_string()),
+                    n2: Some("i".to_string()),
+                },
+                mora: Some(Mora {
+                    relative_accent_position: -2,
+                    position_forward: 3,
+                    position_backward: 3,
+                }),
+                word_prev: None,
+                word_curr: Some(Word {
+                    pos: Some(9),
+                    ctype: None,
+                    cform: None,
+                }),
+                word_next: None,
+                accent_phrase_prev: None,
+                accent_phrase_curr: Some(AccentPhraseCurrent {
+                    mora_count: 5,
+                    accent_position: 5,
+                    is_interrogative: false,
+                    accent_phrase_position_forward: 1,
+                    accent_phrase_position_backward: 1,
+                    mora_position_forward: 1,
+                    mora_position_backward: 5,
+                }),
+                accent_phrase_next: None,
+                breath_group_prev: None,
+                breath_group_curr: Some(BreathGroupCurrent {
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                    breath_group_position_forward: 1,
+                    breath_group_position_backward: 1,
+                    accent_phrase_position_forward: 1,
+                    accent_phrase_position_backward: 1,
+                    mora_position_forward: 1,
+                    mora_position_backward: 5,
+                }),
+                breath_group_next: None,
+                utterance: Utterance {
+                    breath_group_count: 1,
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                },
+            },
+        ),
+        (
+            "n^i-ch+i=w/A:-1+4+2/B:xx-xx_xx/C:09_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:5_5#0_xx@1_1|1_5/G:xx_xx%xx_xx_xx/H:xx_xx/I:1-5@1+1&1-1|1+5/J:xx_xx/K:1+1-5",
+            Label {
+                phoneme: Phoneme {
+                    p2: Some("n".to_string()),
+                    p1: Some("i".to_string()),
+                    c: Some("ch".to_string()),
+                    n1: Some("i".to_string()),
+                    n2: Some("w".to_string()),
+                },
+                mora: Some(Mora {
+                    relative_accent_position: -1,
+                    position_forward: 4,
+                    position_backward: 2,
+                }),
+                word_prev: None,
+                word_curr: Some(Word {
+                    pos: Some(9),
+                    ctype: None,
+                    cform: None,
+                }),
+                word_next: None,
+                accent_phrase_prev: None,
+                accent_phrase_curr: Some(AccentPhraseCurrent {
+                    mora_count: 5,
+                    accent_position: 5,
+                    is_interrogative: false,
+                    accent_phrase_position_forward: 1,
+                    accent_phrase_position_backward: 1,
+                    mora_position_forward: 1,
+                    mora_position_backward: 5,
+                }),
+                accent_phrase_next: None,
+                breath_group_prev: None,
+                breath_group_curr: Some(BreathGroupCurrent {
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                    breath_group_position_forward: 1,
+                    breath_group_position_backward: 1,
+                    accent_phrase_position_forward: 1,
+                    accent_phrase_position_backward: 1,
+                    mora_position_forward: 1,
+                    mora_position_backward: 5,
+                }),
+                breath_group_next: None,
+                utterance: Utterance {
+                    breath_group_count: 1,
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                },
+            },
+        ),
+        (
+            "i^ch-i+w=a/A:-1+4+2/B:xx-xx_xx/C:09_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:5_5#0_xx@1_1|1_5/G:xx_xx%xx_xx_xx/H:xx_xx/I:1-5@1+1&1-1|1+5/J:xx_xx/K:1+1-5",
+            Label {
+                phoneme: Phoneme {
+                    p2: Some("i".to_string()),
+                    p1: Some("ch".to_string()),
+                    c: Some("i".to_string()),
+                    n1: Some("w".to_string()),
+                    n2: Some("a".to_string()),
+                },
+                mora: Some(Mora {
+                    relative_accent_position: -1,
+                    position_forward: 4,
+                    position_backward: 2,
+                }),
+                word_prev: None,
+                word_curr: Some(Word {
+                    pos: Some(9),
+                    ctype: None,
+                    cform: None,
+                }),
+                word_next: None,
+                accent_phrase_prev: None,
+                accent_phrase_curr: Some(AccentPhraseCurrent {
+                    mora_count: 5,
+                    accent_position: 5,
+                    is_interrogative: false,
+                    accent_phrase_position_forward: 1,
+                    accent_phrase_position_backward: 1,
+                    mora_position_forward: 1,
+                    mora_position_backward: 5,
+                }),
+                accent_phrase_next: None,
+                breath_group_prev: None,
+                breath_group_curr: Some(BreathGroupCurrent {
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                    breath_group_position_forward: 1,
+                    breath_group_position_backward: 1,
+                    accent_phrase_position_forward: 1,
+                    accent_phrase_position_backward: 1,
+                    mora_position_forward: 1,
+                    mora_position_backward: 5,
+                }),
+                breath_group_next: None,
+                utterance: Utterance {
+                    breath_group_count: 1,
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                },
+            },
+        ),
+        (
+            "ch^i-w+a=sil/A:0+5+1/B:xx-xx_xx/C:09_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:5_5#0_xx@1_1|1_5/G:xx_xx%xx_xx_xx/H:xx_xx/I:1-5@1+1&1-1|1+5/J:xx_xx/K:1+1-5",
+            Label {
+                phoneme: Phoneme {
+                    p2: Some("ch".to_string()),
+                    p1: Some("i".to_string()),
+                    c: Some("w".to_string()),
+                    n1: Some("a".to_string()),
+                    n2: Some("sil".to_string()),
+                },
+                mora: Some(Mora {
+                    relative_accent_position: 0,
+                    position_forward: 5,
+                    position_backward: 1,
+                }),
+                word_prev: None,
+                word_curr: Some(Word {
+                    pos: Some(9),
+                    ctype: None,
+                    cform: None,
+                }),
+                word_next: None,
+                accent_phrase_prev: None,
+                accent_phrase_curr: Some(AccentPhraseCurrent {
+                    mora_count: 5,
+                    accent_position: 5,
+                    is_interrogative: false,
+                    accent_phrase_position_forward: 1,
+                    accent_phrase_position_backward: 1,
+                    mora_position_forward: 1,
+                    mora_position_backward: 5,
+                }),
+                accent_phrase_next: None,
+                breath_group_prev: None,
+                breath_group_curr: Some(BreathGroupCurrent {
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                    breath_group_position_forward: 1,
+                    breath_group_position_backward: 1,
+                    accent_phrase_position_forward: 1,
+                    accent_phrase_position_backward: 1,
+                    mora_position_forward: 1,
+                    mora_position_backward: 5,
+                }),
+                breath_group_next: None,
+                utterance: Utterance {
+                    breath_group_count: 1,
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                },
+            },
+        ),
+        (
+            "i^w-a+sil=xx/A:0+5+1/B:xx-xx_xx/C:09_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:5_5#0_xx@1_1|1_5/G:xx_xx%xx_xx_xx/H:xx_xx/I:1-5@1+1&1-1|1+5/J:xx_xx/K:1+1-5",
+            Label {
+                phoneme: Phoneme {
+                    p2: Some("i".to_string()),
+                    p1: Some("w".to_string()),
+                    c: Some("a".to_string()),
+                    n1: Some("sil".to_string()),
+                    n2: None,
+                },
+                mora: Some(Mora {
+                    relative_accent_position: 0,
+                    position_forward: 5,
+                    position_backward: 1,
+                }),
+                word_prev: None,
+                word_curr: Some(Word {
+                    pos: Some(9),
+                    ctype: None,
+                    cform: None,
+                }),
+                word_next: None,
+                accent_phrase_prev: None,
+                accent_phrase_curr: Some(AccentPhraseCurrent {
+                    mora_count: 5,
+                    accent_position: 5,
+                    is_interrogative: false,
+                    accent_phrase_position_forward: 1,
+                    accent_phrase_position_backward: 1,
+                    mora_position_forward: 1,
+                    mora_position_backward: 5,
+                }),
+                accent_phrase_next: None,
+                breath_group_prev: None,
+                breath_group_curr: Some(BreathGroupCurrent {
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                    breath_group_position_forward: 1,
+                    breath_group_position_backward: 1,
+                    accent_phrase_position_forward: 1,
+                    accent_phrase_position_backward: 1,
+                    mora_position_forward: 1,
+                    mora_position_backward: 5,
+                }),
+                breath_group_next: None,
+                utterance: Utterance {
+                    breath_group_count: 1,
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                },
+            },
+        ),
+        (
+            "w^a-sil+xx=xx/A:xx+xx+xx/B:xx-xx_xx/C:xx_xx+xx/D:xx+xx_xx/E:5_5!0_xx-xx/F:xx_xx#xx_xx@xx_xx|xx_xx/G:xx_xx%xx_xx_xx/H:1_5/I:xx-xx@xx+xx&xx-xx|xx+xx/J:xx_xx/K:1+1-5",
+            Label {
+                phoneme: Phoneme {
+                    p2: Some("w".to_string()),
+                    p1: Some("a".to_string()),
+                    c: Some("sil".to_string()),
+                    n1: None,
+                    n2: None,
+                },
+                mora: None,
+                word_prev: None,
+                word_curr: None,
+                word_next: None,
+                accent_phrase_prev: Some(AccentPhrasePrevNext {
+                    mora_count: 5,
+                    accent_position: 5,
+                    is_interrogative: false,
+                    is_pause_insertion: None,
+                }),
+                accent_phrase_curr: None,
+                accent_phrase_next: None,
+                breath_group_prev: Some(BreathGroupPrevNext {
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                }),
+                breath_group_curr: None,
+                breath_group_next: None,
+                utterance: Utterance {
+                    breath_group_count: 1,
+                    accent_phrase_count: 1,
+                    mora_count: 5,
+                },
+            },
+        ),
+    ]
+}
diff --git a/src/lib.rs b/src/lib.rs
index 50f101a..9e097aa 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,2 +1,6 @@
 mod fullcontext_label;
 mod parser;
+mod serializer;
+
+#[cfg(test)]
+mod fixture;
diff --git a/src/parser/mod.rs b/src/parser/mod.rs
index 57f5e04..46339a5 100644
--- a/src/parser/mod.rs
+++ b/src/parser/mod.rs
@@ -176,7 +176,7 @@ impl<'a> LabelTokenizer<'a> {
         }
     }
 
-    /// `/F:f1_f2#_f3_f4@_f5_f6|f7_f8`
+    /// `/F:f1_f2#f3_f4@f5_f6|f7_f8`
     fn f(&mut self) -> Result<Option<AccentPhraseCurrent>, ParseError> {
         let f1 = Self::parse_or_xx(self.until("_")?)?;
         let f2 = Self::parse_or_xx(self.until("#")?)?;
diff --git a/src/parser/test.rs b/src/parser/test.rs
index 160970d..70b945c 100644
--- a/src/parser/test.rs
+++ b/src/parser/test.rs
@@ -1,550 +1,9 @@
-use super::*;
+use crate::{fixture::fixtures, fullcontext_label::Label};
 
 #[test]
 fn test_parse() {
-    let tests = [
-        (
-            "xx^xx-sil+k=o/A:xx+xx+xx/B:xx-xx_xx/C:xx_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:xx_xx#xx_xx@xx_xx|xx_xx/G:5_5%0_xx_xx/H:xx_xx/I:xx-xx@xx+xx&xx-xx|xx+xx/J:1_5/K:1+1-5",
-            Label {
-                phoneme: Phoneme {
-                    p2: None,
-                    p1: None,
-                    c: Some("sil".to_string()),
-                    n1: Some("k".to_string()),
-                    n2: Some("o".to_string()),
-                },
-                mora: None,
-                word_prev: None,
-                word_curr: None,
-                word_next: None,
-                accent_phrase_prev: None,
-                accent_phrase_curr: None,
-                accent_phrase_next: Some(AccentPhrasePrevNext {
-                    mora_count: 5,
-                    accent_position: 5,
-                    is_interrogative: false,
-                    is_pause_insertion: None
-                }),
-                breath_group_prev: None,
-                breath_group_curr: None,
-                breath_group_next: Some(BreathGroupPrevNext {
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                }),
-                utterance: Utterance {
-                    breath_group_count: 1,
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                },
-            },
-        ),
-        (
-            "xx^sil-k+o=N/A:-4+1+5/B:xx-xx_xx/C:09_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:5_5#0_xx@1_1|1_5/G:xx_xx%xx_xx_xx/H:xx_xx/I:1-5@1+1&1-1|1+5/J:xx_xx/K:1+1-5",
-            Label {
-                phoneme: Phoneme {
-                    p2: None,
-                    p1: Some("sil".to_string()),
-                    c: Some("k".to_string()),
-                    n1: Some("o".to_string()),
-                    n2: Some("N".to_string()),
-                },
-                mora: Some(Mora {
-                    relative_accent_position: -4,
-                    position_forward: 1,
-                    position_backward: 5,
-                }),
-                word_prev: None,
-                word_curr: Some(Word {
-                    pos: Some(9),
-                    ctype: None,
-                    cform: None,
-                }),
-                word_next: None,
-                accent_phrase_prev: None,
-                accent_phrase_curr: Some(AccentPhraseCurrent {
-                    mora_count: 5,
-                    accent_position: 5,
-                    is_interrogative: false,
-                    accent_phrase_position_forward: 1,
-                    accent_phrase_position_backward: 1,
-                    mora_position_forward: 1,
-                    mora_position_backward: 5,
-                }),
-                accent_phrase_next: None,
-                breath_group_prev: None,
-                breath_group_curr: Some(BreathGroupCurrent {
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                    breath_group_position_forward: 1,
-                    breath_group_position_backward: 1,
-                    accent_phrase_position_forward: 1,
-                    accent_phrase_position_backward: 1,
-                    mora_position_forward: 1,
-                    mora_position_backward: 5,
-                }),
-                breath_group_next: None,
-                utterance: Utterance {
-                    breath_group_count: 1,
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                },
-            },
-        ),
-        (
-            "sil^k-o+N=n/A:-4+1+5/B:xx-xx_xx/C:09_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:5_5#0_xx@1_1|1_5/G:xx_xx%xx_xx_xx/H:xx_xx/I:1-5@1+1&1-1|1+5/J:xx_xx/K:1+1-5",
-            Label {
-                phoneme: Phoneme {
-                    p2: Some("sil".to_string()),
-                    p1: Some("k".to_string()),
-                    c: Some("o".to_string()),
-                    n1: Some("N".to_string()),
-                    n2: Some("n".to_string()),
-                },
-                mora: Some(Mora {
-                    relative_accent_position: -4,
-                    position_forward: 1,
-                    position_backward: 5,
-                }),
-                word_prev: None,
-                word_curr: Some(Word {
-                    pos: Some(9),
-                    ctype: None,
-                    cform: None,
-                }),
-                word_next: None,
-                accent_phrase_prev: None,
-                accent_phrase_curr: Some(AccentPhraseCurrent {
-                    mora_count: 5,
-                    accent_position: 5,
-                    is_interrogative: false,
-                    accent_phrase_position_forward: 1,
-                    accent_phrase_position_backward: 1,
-                    mora_position_forward: 1,
-                    mora_position_backward: 5,
-                }),
-                accent_phrase_next: None,
-                breath_group_prev: None,
-                breath_group_curr: Some(BreathGroupCurrent {
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                    breath_group_position_forward: 1,
-                    breath_group_position_backward: 1,
-                    accent_phrase_position_forward: 1,
-                    accent_phrase_position_backward: 1,
-                    mora_position_forward: 1,
-                    mora_position_backward: 5,
-                }),
-                breath_group_next: None,
-                utterance: Utterance {
-                    breath_group_count: 1,
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                },
-            },
-        ),
-        (
-            "k^o-N+n=i/A:-3+2+4/B:xx-xx_xx/C:09_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:5_5#0_xx@1_1|1_5/G:xx_xx%xx_xx_xx/H:xx_xx/I:1-5@1+1&1-1|1+5/J:xx_xx/K:1+1-5",
-            Label {
-                phoneme: Phoneme {
-                    p2: Some("k".to_string()),
-                    p1: Some("o".to_string()),
-                    c: Some("N".to_string()),
-                    n1: Some("n".to_string()),
-                    n2: Some("i".to_string()),
-                },
-                mora: Some(Mora {
-                    relative_accent_position: -3,
-                    position_forward: 2,
-                    position_backward: 4,
-                }),
-                word_prev: None,
-                word_curr: Some(Word {
-                    pos: Some(9),
-                    ctype: None,
-                    cform: None,
-                }),
-                word_next: None,
-                accent_phrase_prev: None,
-                accent_phrase_curr: Some(AccentPhraseCurrent {
-                    mora_count: 5,
-                    accent_position: 5,
-                    is_interrogative: false,
-                    accent_phrase_position_forward: 1,
-                    accent_phrase_position_backward: 1,
-                    mora_position_forward: 1,
-                    mora_position_backward: 5,
-                }),
-                accent_phrase_next: None,
-                breath_group_prev: None,
-                breath_group_curr: Some(BreathGroupCurrent {
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                    breath_group_position_forward: 1,
-                    breath_group_position_backward: 1,
-                    accent_phrase_position_forward: 1,
-                    accent_phrase_position_backward: 1,
-                    mora_position_forward: 1,
-                    mora_position_backward: 5,
-                }),
-                breath_group_next: None,
-                utterance: Utterance {
-                    breath_group_count: 1,
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                },
-            },
-        ),
-        (
-            "o^N-n+i=ch/A:-2+3+3/B:xx-xx_xx/C:09_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:5_5#0_xx@1_1|1_5/G:xx_xx%xx_xx_xx/H:xx_xx/I:1-5@1+1&1-1|1+5/J:xx_xx/K:1+1-5",
-            Label {
-                phoneme: Phoneme {
-                    p2: Some("o".to_string()),
-                    p1: Some("N".to_string()),
-                    c: Some("n".to_string()),
-                    n1: Some("i".to_string()),
-                    n2: Some("ch".to_string()),
-                },
-                mora: Some(Mora {
-                    relative_accent_position: -2,
-                    position_forward: 3,
-                    position_backward: 3,
-                }),
-                word_prev: None,
-                word_curr: Some(Word {
-                    pos: Some(9),
-                    ctype: None,
-                    cform: None,
-                }),
-                word_next: None,
-                accent_phrase_prev: None,
-                accent_phrase_curr: Some(AccentPhraseCurrent {
-                    mora_count: 5,
-                    accent_position: 5,
-                    is_interrogative: false,
-                    accent_phrase_position_forward: 1,
-                    accent_phrase_position_backward: 1,
-                    mora_position_forward: 1,
-                    mora_position_backward: 5,
-                }),
-                accent_phrase_next: None,
-                breath_group_prev: None,
-                breath_group_curr: Some(BreathGroupCurrent {
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                    breath_group_position_forward: 1,
-                    breath_group_position_backward: 1,
-                    accent_phrase_position_forward: 1,
-                    accent_phrase_position_backward: 1,
-                    mora_position_forward: 1,
-                    mora_position_backward: 5,
-                }),
-                breath_group_next: None,
-                utterance: Utterance {
-                    breath_group_count: 1,
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                },
-            },
-        ),
-        (
-            "N^n-i+ch=i/A:-2+3+3/B:xx-xx_xx/C:09_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:5_5#0_xx@1_1|1_5/G:xx_xx%xx_xx_xx/H:xx_xx/I:1-5@1+1&1-1|1+5/J:xx_xx/K:1+1-5",
-            Label {
-                phoneme: Phoneme {
-                    p2: Some("N".to_string()),
-                    p1: Some("n".to_string()),
-                    c: Some("i".to_string()),
-                    n1: Some("ch".to_string()),
-                    n2: Some("i".to_string()),
-                },
-                mora: Some(Mora {
-                    relative_accent_position: -2,
-                    position_forward: 3,
-                    position_backward: 3,
-                }),
-                word_prev: None,
-                word_curr: Some(Word {
-                    pos: Some(9),
-                    ctype: None,
-                    cform: None,
-                }),
-                word_next: None,
-                accent_phrase_prev: None,
-                accent_phrase_curr: Some(AccentPhraseCurrent {
-                    mora_count: 5,
-                    accent_position: 5,
-                    is_interrogative: false,
-                    accent_phrase_position_forward: 1,
-                    accent_phrase_position_backward: 1,
-                    mora_position_forward: 1,
-                    mora_position_backward: 5,
-                }),
-                accent_phrase_next: None,
-                breath_group_prev: None,
-                breath_group_curr: Some(BreathGroupCurrent {
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                    breath_group_position_forward: 1,
-                    breath_group_position_backward: 1,
-                    accent_phrase_position_forward: 1,
-                    accent_phrase_position_backward: 1,
-                    mora_position_forward: 1,
-                    mora_position_backward: 5,
-                }),
-                breath_group_next: None,
-                utterance: Utterance {
-                    breath_group_count: 1,
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                },
-            },
-        ),
-        (
-            "n^i-ch+i=w/A:-1+4+2/B:xx-xx_xx/C:09_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:5_5#0_xx@1_1|1_5/G:xx_xx%xx_xx_xx/H:xx_xx/I:1-5@1+1&1-1|1+5/J:xx_xx/K:1+1-5",
-            Label {
-                phoneme: Phoneme {
-                    p2: Some("n".to_string()),
-                    p1: Some("i".to_string()),
-                    c: Some("ch".to_string()),
-                    n1: Some("i".to_string()),
-                    n2: Some("w".to_string()),
-                },
-                mora: Some(Mora {
-                    relative_accent_position: -1,
-                    position_forward: 4,
-                    position_backward: 2,
-                }),
-                word_prev: None,
-                word_curr: Some(Word {
-                    pos: Some(9),
-                    ctype: None,
-                    cform: None,
-                }),
-                word_next: None,
-                accent_phrase_prev: None,
-                accent_phrase_curr: Some(AccentPhraseCurrent {
-                    mora_count: 5,
-                    accent_position: 5,
-                    is_interrogative: false,
-                    accent_phrase_position_forward: 1,
-                    accent_phrase_position_backward: 1,
-                    mora_position_forward: 1,
-                    mora_position_backward: 5,
-                }),
-                accent_phrase_next: None,
-                breath_group_prev: None,
-                breath_group_curr: Some(BreathGroupCurrent {
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                    breath_group_position_forward: 1,
-                    breath_group_position_backward: 1,
-                    accent_phrase_position_forward: 1,
-                    accent_phrase_position_backward: 1,
-                    mora_position_forward: 1,
-                    mora_position_backward: 5,
-                }),
-                breath_group_next: None,
-                utterance: Utterance {
-                    breath_group_count: 1,
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                },
-            },
-        ),
-        (
-            "i^ch-i+w=a/A:-1+4+2/B:xx-xx_xx/C:09_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:5_5#0_xx@1_1|1_5/G:xx_xx%xx_xx_xx/H:xx_xx/I:1-5@1+1&1-1|1+5/J:xx_xx/K:1+1-5",
-            Label {
-                phoneme: Phoneme {
-                    p2: Some("i".to_string()),
-                    p1: Some("ch".to_string()),
-                    c: Some("i".to_string()),
-                    n1: Some("w".to_string()),
-                    n2: Some("a".to_string()),
-                },
-                mora: Some(Mora {
-                    relative_accent_position: -1,
-                    position_forward: 4,
-                    position_backward: 2,
-                }),
-                word_prev: None,
-                word_curr: Some(Word {
-                    pos: Some(9),
-                    ctype: None,
-                    cform: None,
-                }),
-                word_next: None,
-                accent_phrase_prev: None,
-                accent_phrase_curr: Some(AccentPhraseCurrent {
-                    mora_count: 5,
-                    accent_position: 5,
-                    is_interrogative: false,
-                    accent_phrase_position_forward: 1,
-                    accent_phrase_position_backward: 1,
-                    mora_position_forward: 1,
-                    mora_position_backward: 5,
-                }),
-                accent_phrase_next: None,
-                breath_group_prev: None,
-                breath_group_curr: Some(BreathGroupCurrent {
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                    breath_group_position_forward: 1,
-                    breath_group_position_backward: 1,
-                    accent_phrase_position_forward: 1,
-                    accent_phrase_position_backward: 1,
-                    mora_position_forward: 1,
-                    mora_position_backward: 5,
-                }),
-                breath_group_next: None,
-                utterance: Utterance {
-                    breath_group_count: 1,
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                },
-            },
-        ),
-        (
-            "ch^i-w+a=sil/A:0+5+1/B:xx-xx_xx/C:09_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:5_5#0_xx@1_1|1_5/G:xx_xx%xx_xx_xx/H:xx_xx/I:1-5@1+1&1-1|1+5/J:xx_xx/K:1+1-5",
-            Label {
-                phoneme: Phoneme {
-                    p2: Some("ch".to_string()),
-                    p1: Some("i".to_string()),
-                    c: Some("w".to_string()),
-                    n1: Some("a".to_string()),
-                    n2: Some("sil".to_string()),
-                },
-                mora: Some(Mora {
-                    relative_accent_position: 0,
-                    position_forward: 5,
-                    position_backward: 1,
-                }),
-                word_prev: None,
-                word_curr: Some(Word {
-                    pos: Some(9),
-                    ctype: None,
-                    cform: None,
-                }),
-                word_next: None,
-                accent_phrase_prev: None,
-                accent_phrase_curr: Some(AccentPhraseCurrent {
-                    mora_count: 5,
-                    accent_position: 5,
-                    is_interrogative: false,
-                    accent_phrase_position_forward: 1,
-                    accent_phrase_position_backward: 1,
-                    mora_position_forward: 1,
-                    mora_position_backward: 5,
-                }),
-                accent_phrase_next: None,
-                breath_group_prev: None,
-                breath_group_curr: Some(BreathGroupCurrent {
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                    breath_group_position_forward: 1,
-                    breath_group_position_backward: 1,
-                    accent_phrase_position_forward: 1,
-                    accent_phrase_position_backward: 1,
-                    mora_position_forward: 1,
-                    mora_position_backward: 5,
-                }),
-                breath_group_next: None,
-                utterance: Utterance {
-                    breath_group_count: 1,
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                },
-            },
-        ),
-        (
-            "i^w-a+sil=xx/A:0+5+1/B:xx-xx_xx/C:09_xx+xx/D:xx+xx_xx/E:xx_xx!xx_xx-xx/F:5_5#0_xx@1_1|1_5/G:xx_xx%xx_xx_xx/H:xx_xx/I:1-5@1+1&1-1|1+5/J:xx_xx/K:1+1-5",
-            Label {
-                phoneme: Phoneme {
-                    p2: Some("i".to_string()),
-                    p1: Some("w".to_string()),
-                    c: Some("a".to_string()),
-                    n1: Some("sil".to_string()),
-                    n2: None,
-                },
-                mora: Some(Mora {
-                    relative_accent_position: 0,
-                    position_forward: 5,
-                    position_backward: 1,
-                }),
-                word_prev: None,
-                word_curr: Some(Word {
-                    pos: Some(9),
-                    ctype: None,
-                    cform: None,
-                }),
-                word_next: None,
-                accent_phrase_prev: None,
-                accent_phrase_curr: Some(AccentPhraseCurrent {
-                    mora_count: 5,
-                    accent_position: 5,
-                    is_interrogative: false,
-                    accent_phrase_position_forward: 1,
-                    accent_phrase_position_backward: 1,
-                    mora_position_forward: 1,
-                    mora_position_backward: 5,
-                }),
-                accent_phrase_next: None,
-                breath_group_prev: None,
-                breath_group_curr: Some(BreathGroupCurrent {
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                    breath_group_position_forward: 1,
-                    breath_group_position_backward: 1,
-                    accent_phrase_position_forward: 1,
-                    accent_phrase_position_backward: 1,
-                    mora_position_forward: 1,
-                    mora_position_backward: 5,
-                }),
-                breath_group_next: None,
-                utterance: Utterance {
-                    breath_group_count: 1,
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                },
-            },
-        ),
-        (
-            "w^a-sil+xx=xx/A:xx+xx+xx/B:xx-xx_xx/C:xx_xx+xx/D:xx+xx_xx/E:5_5!0_xx-xx/F:xx_xx#xx_xx@xx_xx|xx_xx/G:xx_xx%xx_xx_xx/H:1_5/I:xx-xx@xx+xx&xx-xx|xx+xx/J:xx_xx/K:1+1-5",
-            Label {
-                phoneme: Phoneme {
-                    p2: Some("w".to_string()),
-                    p1: Some("a".to_string()),
-                    c: Some("sil".to_string()),
-                    n1: None,
-                    n2: None,
-                },
-                mora: None,
-                word_prev: None,
-                word_curr: None,
-                word_next: None,
-                accent_phrase_prev: Some(AccentPhrasePrevNext {
-                    mora_count: 5,
-                    accent_position: 5,
-                    is_interrogative: false,
-                    is_pause_insertion: None,
-                }),
-                accent_phrase_curr: None,
-                accent_phrase_next: None,
-                breath_group_prev: Some(BreathGroupPrevNext {
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                }),
-                breath_group_curr: None,
-                breath_group_next: None,
-                utterance: Utterance {
-                    breath_group_count: 1,
-                    accent_phrase_count: 1,
-                    mora_count: 5,
-                },
-            },
-        ),
-    ];
-
-    for (input, expected) in tests.iter() {
+    for (input, expected) in fixtures() {
         let actual = input.parse::<Label>().unwrap();
-        assert_eq!(&actual, expected);
+        assert_eq!(actual, expected);
     }
 }
diff --git a/src/serializer/mod.rs b/src/serializer/mod.rs
new file mode 100644
index 0000000..14f8770
--- /dev/null
+++ b/src/serializer/mod.rs
@@ -0,0 +1,318 @@
+use std::fmt::{Display, Formatter, Result, Write};
+
+use crate::fullcontext_label::{
+    AccentPhraseCurrent, AccentPhrasePrevNext, BreathGroupCurrent, BreathGroupPrevNext, Label,
+    Mora, Phoneme, Utterance, Word,
+};
+
+struct Serializer<'a, 'b> {
+    f: &'b mut Formatter<'a>,
+}
+
+impl<'a, 'b> Serializer<'a, 'b> {
+    fn new(f: &'b mut Formatter<'a>) -> Self {
+        Self { f }
+    }
+
+    fn xx(&mut self) -> Result {
+        self.f.write_str("xx")
+    }
+
+    fn all_xx<const N: usize>(&mut self, sep: &[char; N]) -> Result {
+        self.xx()?;
+        for c in sep {
+            self.f.write_char(*c)?;
+            self.xx()?;
+        }
+
+        Ok(())
+    }
+
+    fn or_xx<T: Display>(&mut self, value: &Option<T>) -> Result {
+        match value {
+            Some(v) => v.fmt(self.f),
+            None => self.xx(),
+        }
+    }
+
+    fn d02_or_xx<T: Display>(&mut self, value: &Option<T>) -> Result {
+        match value {
+            Some(v) => write!(self.f, "{:02}", v),
+            None => self.xx(),
+        }
+    }
+
+    fn bool(&mut self, value: bool) -> Result {
+        match value {
+            true => self.f.write_char('1'),
+            false => self.f.write_char('0'),
+        }
+    }
+
+    fn bool_or_xx(&mut self, value: &Option<bool>) -> Result {
+        match value {
+            Some(v) => self.bool(*v),
+            None => self.xx(),
+        }
+    }
+
+    /// `p1ˆp2-p3+p4=p5`
+    fn p(&mut self, phoneme: &Phoneme) -> Result {
+        self.or_xx(&phoneme.p2)?;
+        self.f.write_char('^')?;
+        self.or_xx(&phoneme.p1)?;
+        self.f.write_char('-')?;
+        self.or_xx(&phoneme.c)?;
+        self.f.write_char('+')?;
+        self.or_xx(&phoneme.n1)?;
+        self.f.write_char('=')?;
+        self.or_xx(&phoneme.n2)?;
+
+        Ok(())
+    }
+
+    /// `/A:a1+a2+a3`
+    fn a(&mut self, mora: &Option<Mora>) -> Result {
+        self.f.write_str("/A:")?;
+
+        if let Some(mora) = mora {
+            mora.relative_accent_position.fmt(self.f)?;
+            self.f.write_char('+')?;
+            mora.position_forward.fmt(self.f)?;
+            self.f.write_char('+')?;
+            mora.position_backward.fmt(self.f)?;
+        } else {
+            self.all_xx(&['+', '+'])?;
+        }
+
+        Ok(())
+    }
+
+    /// `/B:b1-b2_b3`
+    fn b(&mut self, word_prev: &Option<Word>) -> Result {
+        self.f.write_str("/B:")?;
+
+        if let Some(word_prev) = word_prev {
+            self.d02_or_xx(&word_prev.pos)?;
+            self.f.write_char('-')?;
+            self.d02_or_xx(&word_prev.ctype)?;
+            self.f.write_char('_')?;
+            self.d02_or_xx(&word_prev.cform)?;
+        } else {
+            self.all_xx(&['-', '_'])?;
+        }
+
+        Ok(())
+    }
+
+    /// `/C:c1_c2+c3`
+    fn c(&mut self, word_curr: &Option<Word>) -> Result {
+        self.f.write_str("/C:")?;
+
+        if let Some(word_curr) = word_curr {
+            self.d02_or_xx(&word_curr.pos)?;
+            self.f.write_char('_')?;
+            self.d02_or_xx(&word_curr.ctype)?;
+            self.f.write_char('+')?;
+            self.d02_or_xx(&word_curr.cform)?;
+        } else {
+            self.all_xx(&['_', '+'])?;
+        }
+
+        Ok(())
+    }
+
+    /// `/D:d1+d2_d3`
+    fn d(&mut self, word_next: &Option<Word>) -> Result {
+        self.f.write_str("/D:")?;
+
+        if let Some(word_next) = word_next {
+            self.d02_or_xx(&word_next.pos)?;
+            self.f.write_char('+')?;
+            self.d02_or_xx(&word_next.ctype)?;
+            self.f.write_char('_')?;
+            self.d02_or_xx(&word_next.cform)?;
+        } else {
+            self.all_xx(&['+', '_'])?;
+        }
+
+        Ok(())
+    }
+
+    ///`/E:e1_e2!e3_e4-e5`
+    fn e(&mut self, accent_phrase_prev: &Option<AccentPhrasePrevNext>) -> Result {
+        self.f.write_str("/E:")?;
+
+        if let Some(accent_phrase_prev) = accent_phrase_prev {
+            accent_phrase_prev.mora_count.fmt(self.f)?;
+            self.f.write_char('_')?;
+            accent_phrase_prev.accent_position.fmt(self.f)?;
+            self.f.write_char('!')?;
+            self.bool(accent_phrase_prev.is_interrogative)?;
+            self.f.write_char('_')?;
+            self.xx()?;
+            self.f.write_char('-')?;
+            self.bool_or_xx(&accent_phrase_prev.is_pause_insertion)?;
+        } else {
+            self.all_xx(&['_', '!', '_', '-'])?;
+        }
+
+        Ok(())
+    }
+
+    /// `/F:f1_f2#f3_f4@f5_f6|f7_f8`
+    fn f(&mut self, accent_phrase_curr: &Option<AccentPhraseCurrent>) -> Result {
+        self.f.write_str("/F:")?;
+
+        if let Some(accent_phrase_curr) = accent_phrase_curr {
+            accent_phrase_curr.mora_count.fmt(self.f)?;
+            self.f.write_char('_')?;
+            accent_phrase_curr.accent_position.fmt(self.f)?;
+            self.f.write_char('#')?;
+            self.bool(accent_phrase_curr.is_interrogative)?;
+            self.f.write_char('_')?;
+            self.xx()?;
+            self.f.write_char('@')?;
+            accent_phrase_curr
+                .accent_phrase_position_forward
+                .fmt(self.f)?;
+            self.f.write_char('_')?;
+            accent_phrase_curr
+                .accent_phrase_position_backward
+                .fmt(self.f)?;
+            self.f.write_char('|')?;
+            accent_phrase_curr.mora_position_forward.fmt(self.f)?;
+            self.f.write_char('_')?;
+            accent_phrase_curr.mora_position_backward.fmt(self.f)?;
+        } else {
+            self.all_xx(&['_', '#', '_', '@', '_', '|', '_'])?;
+        }
+
+        Ok(())
+    }
+
+    /// `/G:g1_g2%g3_g4_g5`
+    fn g(&mut self, accent_phrase_next: &Option<AccentPhrasePrevNext>) -> Result {
+        self.f.write_str("/G:")?;
+
+        if let Some(accent_phrase_next) = accent_phrase_next {
+            accent_phrase_next.mora_count.fmt(self.f)?;
+            self.f.write_char('_')?;
+            accent_phrase_next.accent_position.fmt(self.f)?;
+            self.f.write_char('%')?;
+            self.bool(accent_phrase_next.is_interrogative)?;
+            self.f.write_char('_')?;
+            self.xx()?;
+            self.f.write_char('_')?;
+            self.bool_or_xx(&accent_phrase_next.is_pause_insertion)?;
+        } else {
+            self.all_xx(&['_', '%', '_', '_'])?;
+        }
+
+        Ok(())
+    }
+
+    /// `/H:h1_h2`
+    fn h(&mut self, breath_group_prev: &Option<BreathGroupPrevNext>) -> Result {
+        self.f.write_str("/H:")?;
+
+        if let Some(breath_group_prev) = breath_group_prev {
+            breath_group_prev.accent_phrase_count.fmt(self.f)?;
+            self.f.write_char('_')?;
+            breath_group_prev.mora_count.fmt(self.f)?;
+        } else {
+            self.all_xx(&['_'])?;
+        }
+
+        Ok(())
+    }
+
+    /// `/I:i1-i2@i3+i4&i5-i6|i7+i8`
+    fn i(&mut self, breath_group_curr: &Option<BreathGroupCurrent>) -> Result {
+        self.f.write_str("/I:")?;
+
+        if let Some(breath_group_curr) = breath_group_curr {
+            breath_group_curr.accent_phrase_count.fmt(self.f)?;
+            self.f.write_char('-')?;
+            breath_group_curr.mora_count.fmt(self.f)?;
+            self.f.write_char('@')?;
+            breath_group_curr
+                .breath_group_position_forward
+                .fmt(self.f)?;
+            self.f.write_char('+')?;
+            breath_group_curr
+                .breath_group_position_backward
+                .fmt(self.f)?;
+            self.f.write_char('&')?;
+            breath_group_curr
+                .accent_phrase_position_forward
+                .fmt(self.f)?;
+            self.f.write_char('-')?;
+            breath_group_curr
+                .accent_phrase_position_backward
+                .fmt(self.f)?;
+            self.f.write_char('|')?;
+            breath_group_curr.mora_position_forward.fmt(self.f)?;
+            self.f.write_char('+')?;
+            breath_group_curr.mora_position_backward.fmt(self.f)?;
+        } else {
+            self.all_xx(&['-', '@', '+', '&', '-', '|', '+'])?;
+        }
+
+        Ok(())
+    }
+
+    /// `/J:j1_j2`
+    fn j(&mut self, breath_group_next: &Option<BreathGroupPrevNext>) -> Result {
+        self.f.write_str("/J:")?;
+
+        if let Some(breath_group_next) = breath_group_next {
+            breath_group_next.accent_phrase_count.fmt(self.f)?;
+            self.f.write_char('_')?;
+            breath_group_next.mora_count.fmt(self.f)?;
+        } else {
+            self.all_xx(&['_'])?;
+        }
+
+        Ok(())
+    }
+
+    /// `/K:k1+k2-k3`
+    fn k(&mut self, utterance: &Utterance) -> Result {
+        self.f.write_str("/K:")?;
+
+        utterance.breath_group_count.fmt(self.f)?;
+        self.f.write_char('+')?;
+        utterance.accent_phrase_count.fmt(self.f)?;
+        self.f.write_char('-')?;
+        utterance.mora_count.fmt(self.f)?;
+
+        Ok(())
+    }
+
+    fn fmt(&mut self, label: &Label) -> Result {
+        self.p(&label.phoneme)?;
+        self.a(&label.mora)?;
+        self.b(&label.word_prev)?;
+        self.c(&label.word_curr)?;
+        self.d(&label.word_next)?;
+        self.e(&label.accent_phrase_prev)?;
+        self.f(&label.accent_phrase_curr)?;
+        self.g(&label.accent_phrase_next)?;
+        self.h(&label.breath_group_prev)?;
+        self.i(&label.breath_group_curr)?;
+        self.j(&label.breath_group_next)?;
+        self.k(&label.utterance)?;
+
+        Ok(())
+    }
+}
+
+impl Display for Label {
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+        Serializer::new(f).fmt(self)
+    }
+}
+
+#[cfg(test)]
+mod test;
diff --git a/src/serializer/test.rs b/src/serializer/test.rs
new file mode 100644
index 0000000..2b9744e
--- /dev/null
+++ b/src/serializer/test.rs
@@ -0,0 +1,9 @@
+use crate::fixture::fixtures;
+
+#[test]
+fn test_serialize() {
+    for (expected, label) in fixtures() {
+        let actual = label.to_string();
+        assert_eq!(actual, expected);
+    }
+}