cmd/gofmt, go/format: refactor common pieces into internal/format
cmd/gofmt and go/format had 3 functions (parse, format and isSpace)
that had to be kept in-sync.
This CL extracts these 3 functions and refactors them into a new
internal/format package.
This CL is just code reorganization with no behavior nor semantic
change.
Change-Id: I593f24e9d3cadbbd9559a67e3b1d2ff190b4fd90
Reviewed-on: https://go-review.googlesource.com/6760
Reviewed-by: Robert Griesemer <gri@golang.org>
diff --git a/src/cmd/gofmt/gofmt.go b/src/cmd/gofmt/gofmt.go
index 81da21f..b2805ac 100644
--- a/src/cmd/gofmt/gofmt.go
+++ b/src/cmd/gofmt/gofmt.go
@@ -13,6 +13,7 @@
"go/printer"
"go/scanner"
"go/token"
+ "internal/format"
"io"
"io/ioutil"
"os"
@@ -87,7 +88,7 @@
return err
}
- file, sourceAdj, indentAdj, err := parse(fileSet, filename, src, stdin)
+ file, sourceAdj, indentAdj, err := format.Parse(fileSet, filename, src, stdin)
if err != nil {
return err
}
@@ -106,7 +107,7 @@
simplify(file)
}
- res, err := format(fileSet, file, sourceAdj, indentAdj, src, printer.Config{Mode: printerMode, Tabwidth: tabWidth})
+ res, err := format.Format(fileSet, file, sourceAdj, indentAdj, src, printer.Config{Mode: printerMode, Tabwidth: tabWidth})
if err != nil {
return err
}
@@ -234,154 +235,3 @@
return
}
-
-// ----------------------------------------------------------------------------
-// Support functions
-//
-// The functions parse, format, and isSpace below are identical to the
-// respective functions in src/go/format/format.go - keep them in sync!
-//
-// TODO(gri) Factor out this functionality, eventually.
-
-// 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.
- fsrc := append(append([]byte("package p; func _() {"), src...), '\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 _() {"):]
- src = src[:len(src)-(indent+len("\n}\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
-}
-
-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 237b860..df9a878 100644
--- a/src/cmd/gofmt/long_test.go
+++ b/src/cmd/gofmt/long_test.go
@@ -15,6 +15,7 @@
"go/ast"
"go/printer"
"go/token"
+ "internal/format"
"io"
"os"
"path/filepath"
@@ -32,7 +33,7 @@
)
func gofmt(fset *token.FileSet, filename string, src *bytes.Buffer) error {
- f, _, _, err := parse(fset, filename, src.Bytes(), false)
+ f, _, _, err := format.Parse(fset, filename, src.Bytes(), false)
if err != nil {
return err
}
@@ -60,7 +61,7 @@
// exclude files w/ syntax errors (typically test cases)
fset := token.NewFileSet()
- if _, _, _, err = parse(fset, filename, b1.Bytes(), false); err != nil {
+ if _, _, _, err = format.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 668a42d..1adfd7d 100644
--- a/src/go/format/format.go
+++ b/src/go/format/format.go
@@ -12,8 +12,8 @@
"go/parser"
"go/printer"
"go/token"
+ "internal/format"
"io"
- "strings"
)
var config = printer.Config{Mode: printer.UseSpaces | printer.TabIndent, Tabwidth: 8}
@@ -82,7 +82,7 @@
//
func Source(src []byte) ([]byte, error) {
fset := token.NewFileSet()
- file, sourceAdj, indentAdj, err := parse(fset, "", src, true)
+ file, sourceAdj, indentAdj, err := format.Parse(fset, "", src, true)
if err != nil {
return nil, err
}
@@ -93,7 +93,7 @@
ast.SortImports(fset, file)
}
- return format(fset, file, sourceAdj, indentAdj, src, config)
+ return format.Format(fset, file, sourceAdj, indentAdj, src, config)
}
func hasUnsortedImports(file *ast.File) bool {
@@ -113,154 +113,3 @@
}
return false
}
-
-// ----------------------------------------------------------------------------
-// Support functions
-//
-// The functions parse, format, and isSpace below are identical to the
-// respective functions in cmd/gofmt/gofmt.go - keep them in sync!
-//
-// TODO(gri) Factor out this functionality, eventually.
-
-// 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.
- fsrc := append(append([]byte("package p; func _() {"), src...), '\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 _() {"):]
- src = src[:len(src)-(indent+len("\n}\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
-}
-
-func isSpace(b byte) bool {
- return b == ' ' || b == '\t' || b == '\n' || b == '\r'
-}
diff --git a/src/internal/format/format.go b/src/internal/format/format.go
new file mode 100644
index 0000000..f8812ff
--- /dev/null
+++ b/src/internal/format/format.go
@@ -0,0 +1,161 @@
+// 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.
+
+package format
+
+import (
+ "bytes"
+ "go/ast"
+ "go/parser"
+ "go/printer"
+ "go/token"
+ "strings"
+)
+
+const parserMode = parser.ParseComments
+
+// 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.
+ fsrc := append(append([]byte("package p; func _() {"), src...), '\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 _() {"):]
+ src = src[:len(src)-(indent+len("\n}\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'
+}
