Support pwsh format for show-env (#411)

.github/.cspell/project-dictionary.txt

@@ -17,6 +17,7 @@ nextest
 notcovered
 profdata
 profraw
+pwsh
 rmeta
 rustfilt
 rustix

README.md

@@ -479,6 +479,12 @@ Note: cargo-llvm-cov subcommands other than `report` and `clean` may not work co
 
 Note: To include coverage for doctests you also need to pass `--doctests` to both `cargo llvm-cov show-env` and `cargo llvm-cov report`.
 
+> The same thing can be achieved in PowerShell 6+ by substituting the source command with:
+>
+> ```powershell
+> Invoke-Expression (cargo llvm-cov show-env --with-pwsh-env-prefix | Out-String)
+> ```
+
 ### Exclude file from coverage
 
 To exclude specific file patterns from the report, use the `--ignore-filename-regex` option.

docs/cargo-llvm-cov-show-env.txt

@@ -8,6 +8,10 @@ OPTIONS:
         --export-prefix
             Prepend "export " to each line, so that the output is suitable to be sourced by bash
 
+        --with-pwsh-env-prefix
+            Unicode escape and double quote values + prepend "$env:", so that the output is suitable
+            to be used with Invoke-Expression in PowerShell 6+.
+
         --doctests
             Including doc tests (unstable)
 

src/cli.rs

@@ -370,9 +370,60 @@ impl LlvmCovOptions {
 }
 
 #[derive(Debug, Clone)]
-pub(crate) struct ShowEnvOptions {
+pub(crate) enum ShowEnvFormat {
+    /// Each line: key=<escaped value>, escaped using [`shell_escape::escape`].
+    EscapedKeyValuePair,
     /// Prepend "export " to each line, so that the output is suitable to be sourced by bash.
-    pub(crate) export_prefix: bool,
+    UnixExport,
+    /// Each value: "$env:{key}={value}", where {value} is PowerShell Unicode escaped e.g. "`u{72}".
+    Pwsh,
+}
+
+impl ShowEnvFormat {
+    pub(crate) fn new(export_prefix: bool, with_pwsh_env_prefix: bool) -> Result<Self> {
+        if export_prefix && with_pwsh_env_prefix {
+            conflicts("--export-prefix", "--with-pwsh-env-prefix")?;
+        }
+
+        Ok(if export_prefix {
+            ShowEnvFormat::UnixExport
+        } else if with_pwsh_env_prefix {
+            ShowEnvFormat::Pwsh
+        } else {
+            ShowEnvFormat::EscapedKeyValuePair
+        })
+    }
+
+    pub(crate) fn export_string(&self, key: &str, value: &str) -> String {
+        match self {
+            ShowEnvFormat::EscapedKeyValuePair => {
+                format!("{key}={}", shell_escape::escape(value.into()))
+            }
+            ShowEnvFormat::UnixExport => {
+                format!("export {key}={}", shell_escape::escape(value.into()))
+            }
+            ShowEnvFormat::Pwsh => {
+                // PowerShell 6+ expects encoded UTF-8 text. Some env vars like CARGO_ENCODED_RUSTFLAGS
+                // have non-printable binary characters. We can work around this and any other escape
+                // related considerations by just escaping all characters. Rust's Unicode escape is
+                // of form "\u{<code>}", but PowerShell expects "`u{<code>}". A replace call fixes
+                // this.
+                let value = value.escape_unicode().to_string().replace('\\', "`");
+                format!("$env:{key}=\"{value}\"")
+            }
+        }
+    }
+}
+
+impl Default for ShowEnvFormat {
+    fn default() -> Self {
+        Self::EscapedKeyValuePair
+    }
+}
+
+#[derive(Debug, Clone)]
+pub(crate) struct ShowEnvOptions {
+    pub(crate) show_env_format: ShowEnvFormat,
 }
 
 // https://doc.rust-lang.org/nightly/cargo/commands/cargo-test.html#manifest-options
@@ -532,6 +583,7 @@ impl Args {
 
         // show-env options
         let mut export_prefix = false;
+        let mut with_pwsh_env_prefix = false;
 
         // options ambiguous between nextest-related and others
         let mut profile = None;
@@ -711,6 +763,7 @@ impl Args {
 
                 // show-env options
                 Long("export-prefix") => parse_flag!(export_prefix),
+                Long("with-pwsh-env-prefix") => parse_flag!(with_pwsh_env_prefix),
 
                 // ambiguous between nextest-related and others will be handled later
                 Long("archive-file") => parse_opt_passthrough!(archive_file),
@@ -814,14 +867,18 @@ impl Args {
         term::set_coloring(&mut color);
 
         // unexpected options
-        match subcommand {
-            Subcommand::ShowEnv => {}
+        let show_env_format = match subcommand {
+            Subcommand::ShowEnv => ShowEnvFormat::new(export_prefix, with_pwsh_env_prefix)?,
             _ => {
                 if export_prefix {
                     unexpected("--export-prefix", subcommand)?;
                 }
+                if with_pwsh_env_prefix {
+                    unexpected("--with-pwsh-env-prefix", subcommand)?;
+                }
+                ShowEnvFormat::default()
             }
-        }
+        };
         if doc || doctests {
             let flag = if doc { "--doc" } else { "--doctests" };
             match subcommand {
@@ -1211,7 +1268,7 @@ impl Args {
                 branch,
                 mcdc,
             },
-            show_env: ShowEnvOptions { export_prefix },
+            show_env: ShowEnvOptions { show_env_format },
             doctests,
             ignore_run_fail,
             lib,

src/main.rs

@@ -160,8 +160,7 @@ struct ShowEnvWriter<W: io::Write> {
 
 impl<W: io::Write> EnvTarget for ShowEnvWriter<W> {
     fn set(&mut self, key: &str, value: &str) -> Result<()> {
-        let prefix = if self.options.export_prefix { "export " } else { "" };
-        writeln!(self.writer, "{prefix}{key}={}", shell_escape::escape(value.into()))
+        writeln!(self.writer, "{}", self.options.show_env_format.export_string(key, value))
             .context("failed to write env to stdout")
     }
     fn unset(&mut self, key: &str) -> Result<()> {

tests/test.rs

@@ -6,6 +6,7 @@ mod auxiliary;
 
 use std::path::Path;
 
+use cargo_config2::Flags;
 use fs_err as fs;
 
 use self::auxiliary::{
@@ -286,6 +287,25 @@ fn open_report() {
 fn show_env() {
     cargo_llvm_cov("show-env").assert_success().stdout_not_contains("export");
     cargo_llvm_cov("show-env").arg("--export-prefix").assert_success().stdout_contains("export");
+
+    let mut flags = Flags::default();
+    flags.push("--deny warnings");
+    flags.push("--cfg=tests");
+    let flags = flags.encode().unwrap();
+
+    cargo_llvm_cov("show-env")
+        .env("CARGO_ENCODED_RUSTFLAGS", flags)
+        .arg("--with-pwsh-env-prefix")
+        .assert_success()
+        // Verify the prefix related content + the encoding of "--"
+        .stdout_contains("$env:CARGO_ENCODED_RUSTFLAGS=\"`u{2d}`u{2d}")
+        // Verify binary character didn't lead to incompatible output for pwsh
+        .stdout_contains("`u{1f}");
+    cargo_llvm_cov("show-env")
+        .arg("--export-prefix")
+        .arg("--with-pwsh-env-prefix")
+        .assert_failure()
+        .stderr_contains("may not be used together with");
 }
 
 #[test]
@@ -298,6 +318,10 @@ fn invalid_arg() {
                 .arg("--export-prefix")
                 .assert_failure()
                 .stderr_contains("invalid option '--export-prefix'");
+            cargo_llvm_cov(subcommand)
+                .arg("--with-pwsh-env-prefix")
+                .assert_failure()
+                .stderr_contains("invalid option '--with-pwsh-env-prefix'");
         }
         if !matches!(subcommand, "" | "test") {
             if matches!(subcommand, "nextest" | "nextest-archive") {