chore: use gofumpt (#196)

## Overview

Unify formatting with `celestia-node` and other Celestia projects in the
future.

.golangci.yml

@@ -0,0 +1,84 @@
+run:
+  timeout: 5m
+
+linters:
+  enable:
+    - bidichk
+    - bodyclose
+     # - depguard as of v1.54.2, the default config throws errors on our repo
+    - dogsled
+    - dupl
+    - errcheck
+    - errorlint
+    # - funlen
+    # - gochecknoglobals
+    # - gochecknoinits
+    - exportloopref
+    - gocheckcompilerdirectives
+    - goconst
+    - gocritic
+    # - gocyclo
+    # - godox
+    - gofmt
+    - gofumpt
+    - goimports
+    # - golint - deprecated since v1.41. revive will be used instead
+    - revive
+    - gosec
+    - gosimple
+    - govet
+    - ineffassign
+    # - interfacer
+    - lll
+    - loggercheck
+    - misspell
+    # - maligned
+    - nakedret
+    - nilerr
+    - nilnil
+    - nolintlint
+    - prealloc
+    - protogetter
+    # - scopelint - deprecated since v1.39. exportloopref will be used instead
+    - exportloopref
+    - staticcheck
+    - stylecheck
+    - typecheck
+    - unconvert
+    # - unparam
+    - unused
+    # - whitespace
+    # - wsl
+    # - gocognit
+    - wastedassign
+    - whitespace
+    - nolintlint
+    - asciicheck
+    - dupword
+
+issues:
+  exclude-rules:
+    - path: _test\.go
+      linters:
+        - gosec
+        - revive
+    - linters:
+        - lll
+      source: "https://"
+  max-same-issues: 50
+
+linters-settings:
+  dogsled:
+    max-blank-identifiers: 3
+  golint:
+    min-confidence: 0
+  maligned:
+    suggest-new: true
+  misspell:
+    locale: US
+  goimports:
+    local-prefixes: github.com/celestiaorg
+  dupl:
+    threshold: 200
+  gofumpt:
+    extra-rules: true

Makefile

@@ -16,8 +16,9 @@ deps:
 ## fmt: Formats only *.go (excluding *.pb.go *pb_test.go). Runs `gofmt & goimports` internally.
 fmt: sort-imports
 	@find . -name '*.go' -type f -not -path "*.git*" -not -name '*.pb.go' -not -name '*pb_test.go' | xargs gofmt -w -s
-	@find . -name '*.go' -type f -not -path "*.git*"  -not -name '*.pb.go' -not -name '*pb_test.go' | xargs goimports -w -local github.com/celestiaorg
+	@find . -name '*.go' -type f -not -path "*.git*" -not -name '*.pb.go' -not -name '*pb_test.go' | xargs goimports -w -local github.com/celestiaorg
 	@go mod tidy
+	@gofumpt -w -extra .
 	@cfmt -w -m=100 ./...
 	@markdownlint --fix --quiet --config .markdownlint.yaml .
 .PHONY: sort-imports

header.go

@@ -12,7 +12,7 @@ type Header[H any] interface {
 	// New creates new instance of a header.
 	// It exists to overcome limitation of Go's type system.
 	// See:
-	//https://go.googlesource.com/proposal/+/refs/heads/master/design/43651-type-parameters.md#pointer-method-example
+	// https://go.googlesource.com/proposal/+/refs/heads/master/design/43651-type-parameters.md#pointer-method-example
 	New() H
 	// IsZero reports whether Header is a zero value of it's concrete type.
 	IsZero() bool

p2p/server.go

@@ -19,9 +19,7 @@ import (
 	p2p_pb "github.com/celestiaorg/go-header/p2p/pb"
 )
 
-var (
-	tracerServ = otel.Tracer("header/server")
-)
+var tracerServ = otel.Tracer("header/server")
 
 // ExchangeServer represents the server-side component for
 // responding to inbound header-related requests.

p2p/session.go

@@ -18,9 +18,7 @@ import (
 	p2p_pb "github.com/celestiaorg/go-header/p2p/pb"
 )
 
-var (
-	tracerSession = otel.Tracer("header/p2p-session")
-)
+var tracerSession = otel.Tracer("header/p2p-session")
 
 // errEmptyResponse means that server side closes the connection without sending at least 1
 // response.

store/keys.go

@@ -8,9 +8,7 @@ import (
 	"github.com/celestiaorg/go-header"
 )
 
-var (
-	headKey = datastore.NewKey("head")
-)
+var headKey = datastore.NewKey("head")
 
 func heightKey(h uint64) datastore.Key {
 	return datastore.NewKey(strconv.Itoa(int(h)))

sync/sync_head_test.go

@@ -45,7 +45,6 @@ func TestSyncer_incomingNetworkHeadRaces(t *testing.T) {
 
 	wg.Wait()
 	assert.EqualValues(t, 1, hits.Load())
-
 }
 
 // TestSyncer_HeadWithTrustedHead tests whether the syncer
@@ -122,12 +121,12 @@ func (t *wrappedGetter) Head(ctx context.Context, options ...header.HeadOption[*
 }
 
 func (t *wrappedGetter) Get(ctx context.Context, hash header.Hash) (*headertest.DummyHeader, error) {
-	//TODO implement me
+	// TODO implement me
 	panic("implement me")
 }
 
 func (t *wrappedGetter) GetByHeight(ctx context.Context, u uint64) (*headertest.DummyHeader, error) {
-	//TODO implement me
+	// TODO implement me
 	panic("implement me")
 }
 
@@ -136,6 +135,6 @@ func (t *wrappedGetter) GetRangeByHeight(
 	from *headertest.DummyHeader,
 	to uint64,
 ) ([]*headertest.DummyHeader, error) {
-	//TODO implement me
+	// TODO implement me
 	panic("implement me")
 }