From: Robert Griesemer Date: Mon, 28 Sep 2015 21:42:21 +0000 (-0700) Subject: go/format, cmd/gofmt: avoid dependency on internal package format X-Git-Tag: go1.6beta1~951 X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=a4fc3512ba85125d51e5e27491a6dd331cd2599b;p=gostls13.git go/format, cmd/gofmt: avoid dependency on internal package format Fixes #11844. Change-Id: I32edd39e79f7c9bdc132c49bd06081f35dac245d Reviewed-on: https://go-review.googlesource.com/15114 Reviewed-by: Alan Donovan --- diff --git a/src/cmd/gofmt/gofmt.go b/src/cmd/gofmt/gofmt.go index b2805ac05f..cfebeffe4a 100644 --- a/src/cmd/gofmt/gofmt.go +++ b/src/cmd/gofmt/gofmt.go @@ -13,7 +13,6 @@ import ( "go/printer" "go/scanner" "go/token" - "internal/format" "io" "io/ioutil" "os" @@ -88,7 +87,7 @@ func processFile(filename string, in io.Reader, out io.Writer, stdin bool) error return err } - file, sourceAdj, indentAdj, err := format.Parse(fileSet, filename, src, stdin) + file, sourceAdj, indentAdj, err := parse(fileSet, filename, src, stdin) if err != nil { return err } @@ -107,7 +106,7 @@ func processFile(filename string, in io.Reader, out io.Writer, stdin bool) error simplify(file) } - res, err := format.Format(fileSet, file, sourceAdj, indentAdj, src, printer.Config{Mode: printerMode, Tabwidth: tabWidth}) + res, err := format(fileSet, file, sourceAdj, indentAdj, src, printer.Config{Mode: printerMode, Tabwidth: tabWidth}) if err != nil { return err } diff --git a/src/cmd/gofmt/internal.go b/src/cmd/gofmt/internal.go new file mode 100644 index 0000000000..fc7f976af9 --- /dev/null +++ b/src/cmd/gofmt/internal.go @@ -0,0 +1,166 @@ +// Copyright 2015 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// TODO(gri): This file and the file src/go/format/internal.go are +// the same (but for this comment and the package name). Do not modify +// one without the other. Determine if we can factor out functionality +// in a public API. See also #11844 for context. + +package main + +import ( + "bytes" + "go/ast" + "go/parser" + "go/printer" + "go/token" + "strings" +) + +// parse parses src, which was read from the named file, +// as a Go source file, declaration, or statement list. +func parse(fset *token.FileSet, filename string, src []byte, fragmentOk bool) ( + file *ast.File, + sourceAdj func(src []byte, indent int) []byte, + indentAdj int, + err error, +) { + // Try as whole source file. + file, err = parser.ParseFile(fset, filename, src, parserMode) + // If there's no error, return. If the error is that the source file didn't begin with a + // package line and source fragments are ok, fall through to + // try as a source fragment. Stop and return on any other error. + if err == nil || !fragmentOk || !strings.Contains(err.Error(), "expected 'package'") { + return + } + + // If this is a declaration list, make it a source file + // by inserting a package clause. + // Insert using a ;, not a newline, so that the line numbers + // in psrc match the ones in src. + psrc := append([]byte("package p;"), src...) + file, err = parser.ParseFile(fset, filename, psrc, parserMode) + if err == nil { + sourceAdj = func(src []byte, indent int) []byte { + // Remove the package clause. + // Gofmt has turned the ; into a \n. + src = src[indent+len("package p\n"):] + return bytes.TrimSpace(src) + } + return + } + // If the error is that the source file didn't begin with a + // declaration, fall through to try as a statement list. + // Stop and return on any other error. + if !strings.Contains(err.Error(), "expected declaration") { + return + } + + // If this is a statement list, make it a source file + // by inserting a package clause and turning the list + // into a function body. This handles expressions too. + // Insert using a ;, not a newline, so that the line numbers + // in fsrc match the ones in src. Add an extra '\n' before the '}' + // to make sure comments are flushed before the '}'. + fsrc := append(append([]byte("package p; func _() {"), src...), '\n', '\n', '}') + file, err = parser.ParseFile(fset, filename, fsrc, parserMode) + if err == nil { + sourceAdj = func(src []byte, indent int) []byte { + // Cap adjusted indent to zero. + if indent < 0 { + indent = 0 + } + // Remove the wrapping. + // Gofmt has turned the ; into a \n\n. + // There will be two non-blank lines with indent, hence 2*indent. + src = src[2*indent+len("package p\n\nfunc _() {"):] + // Remove only the "}\n" suffix: remaining whitespaces will be trimmed anyway + src = src[:len(src)-len("}\n")] + return bytes.TrimSpace(src) + } + // Gofmt has also indented the function body one level. + // Adjust that with indentAdj. + indentAdj = -1 + } + + // Succeeded, or out of options. + return +} + +// format formats the given package file originally obtained from src +// and adjusts the result based on the original source via sourceAdj +// and indentAdj. +func format( + fset *token.FileSet, + file *ast.File, + sourceAdj func(src []byte, indent int) []byte, + indentAdj int, + src []byte, + cfg printer.Config, +) ([]byte, error) { + if sourceAdj == nil { + // Complete source file. + var buf bytes.Buffer + err := cfg.Fprint(&buf, fset, file) + if err != nil { + return nil, err + } + return buf.Bytes(), nil + } + + // Partial source file. + // Determine and prepend leading space. + i, j := 0, 0 + for j < len(src) && isSpace(src[j]) { + if src[j] == '\n' { + i = j + 1 // byte offset of last line in leading space + } + j++ + } + var res []byte + res = append(res, src[:i]...) + + // Determine and prepend indentation of first code line. + // Spaces are ignored unless there are no tabs, + // in which case spaces count as one tab. + indent := 0 + hasSpace := false + for _, b := range src[i:j] { + switch b { + case ' ': + hasSpace = true + case '\t': + indent++ + } + } + if indent == 0 && hasSpace { + indent = 1 + } + for i := 0; i < indent; i++ { + res = append(res, '\t') + } + + // Format the source. + // Write it without any leading and trailing space. + cfg.Indent = indent + indentAdj + var buf bytes.Buffer + err := cfg.Fprint(&buf, fset, file) + if err != nil { + return nil, err + } + res = append(res, sourceAdj(buf.Bytes(), cfg.Indent)...) + + // Determine and append trailing space. + i = len(src) + for i > 0 && isSpace(src[i-1]) { + i-- + } + return append(res, src[i:]...), nil +} + +// isSpace reports whether the byte is a space character. +// isSpace defines a space as being among the following bytes: ' ', '\t', '\n' and '\r'. +func isSpace(b byte) bool { + return b == ' ' || b == '\t' || b == '\n' || b == '\r' +} diff --git a/src/cmd/gofmt/long_test.go b/src/cmd/gofmt/long_test.go index df9a878df4..237b86021b 100644 --- a/src/cmd/gofmt/long_test.go +++ b/src/cmd/gofmt/long_test.go @@ -15,7 +15,6 @@ import ( "go/ast" "go/printer" "go/token" - "internal/format" "io" "os" "path/filepath" @@ -33,7 +32,7 @@ var ( ) func gofmt(fset *token.FileSet, filename string, src *bytes.Buffer) error { - f, _, _, err := format.Parse(fset, filename, src.Bytes(), false) + f, _, _, err := parse(fset, filename, src.Bytes(), false) if err != nil { return err } @@ -61,7 +60,7 @@ func testFile(t *testing.T, b1, b2 *bytes.Buffer, filename string) { // exclude files w/ syntax errors (typically test cases) fset := token.NewFileSet() - if _, _, _, err = format.Parse(fset, filename, b1.Bytes(), false); err != nil { + if _, _, _, err = parse(fset, filename, b1.Bytes(), false); err != nil { if *verbose { fmt.Fprintf(os.Stderr, "ignoring %s\n", err) } diff --git a/src/go/format/format.go b/src/go/format/format.go index 1adfd7d45e..b9cacfebd8 100644 --- a/src/go/format/format.go +++ b/src/go/format/format.go @@ -12,7 +12,6 @@ import ( "go/parser" "go/printer" "go/token" - "internal/format" "io" ) @@ -82,7 +81,7 @@ func Node(dst io.Writer, fset *token.FileSet, node interface{}) error { // func Source(src []byte) ([]byte, error) { fset := token.NewFileSet() - file, sourceAdj, indentAdj, err := format.Parse(fset, "", src, true) + file, sourceAdj, indentAdj, err := parse(fset, "", src, true) if err != nil { return nil, err } @@ -93,7 +92,7 @@ func Source(src []byte) ([]byte, error) { ast.SortImports(fset, file) } - return format.Format(fset, file, sourceAdj, indentAdj, src, config) + return format(fset, file, sourceAdj, indentAdj, src, config) } func hasUnsortedImports(file *ast.File) bool { diff --git a/src/internal/format/format.go b/src/go/format/internal.go similarity index 86% rename from src/internal/format/format.go rename to src/go/format/internal.go index a8270ba669..2850a43068 100644 --- a/src/internal/format/format.go +++ b/src/go/format/internal.go @@ -2,6 +2,11 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. +// TODO(gri): This file and the file src/cmd/gofmt/internal.go are +// the same (but for this comment and the package name). Do not modify +// one without the other. Determine if we can factor out functionality +// in a public API. See also #11844 for context. + package format import ( @@ -13,11 +18,9 @@ import ( "strings" ) -const parserMode = parser.ParseComments - -// Parse parses src, which was read from the named file, +// parse parses src, which was read from the named file, // as a Go source file, declaration, or statement list. -func Parse(fset *token.FileSet, filename string, src []byte, fragmentOk bool) ( +func parse(fset *token.FileSet, filename string, src []byte, fragmentOk bool) ( file *ast.File, sourceAdj func(src []byte, indent int) []byte, indentAdj int, @@ -85,10 +88,10 @@ func Parse(fset *token.FileSet, filename string, src []byte, fragmentOk bool) ( return } -// Format formats the given package file originally obtained from src +// format formats the given package file originally obtained from src // and adjusts the result based on the original source via sourceAdj // and indentAdj. -func Format( +func format( fset *token.FileSet, file *ast.File, sourceAdj func(src []byte, indent int) []byte, @@ -109,7 +112,7 @@ func Format( // Partial source file. // Determine and prepend leading space. i, j := 0, 0 - for j < len(src) && IsSpace(src[j]) { + for j < len(src) && isSpace(src[j]) { if src[j] == '\n' { i = j + 1 // byte offset of last line in leading space } @@ -150,14 +153,14 @@ func Format( // Determine and append trailing space. i = len(src) - for i > 0 && IsSpace(src[i-1]) { + for i > 0 && isSpace(src[i-1]) { i-- } return append(res, src[i:]...), nil } -// IsSpace reports whether the byte is a space character. -// IsSpace defines a space as being among the following bytes: ' ', '\t', '\n' and '\r'. -func IsSpace(b byte) bool { +// isSpace reports whether the byte is a space character. +// isSpace defines a space as being among the following bytes: ' ', '\t', '\n' and '\r'. +func isSpace(b byte) bool { return b == ' ' || b == '\t' || b == '\n' || b == '\r' }