go/printer, gofmt: rely on existing line breaks when formatting expression lists
No impact on existing sources.
Fixes #1632.
R=rsc
CC=golang-dev
https://golang.org/cl/4271083
diff --git a/src/pkg/go/printer/nodes.go b/src/pkg/go/printer/nodes.go
index 8f0d74c..2f12038 100644
--- a/src/pkg/go/printer/nodes.go
+++ b/src/pkg/go/printer/nodes.go
@@ -160,19 +160,7 @@
// the first linebreak is always a formfeed since this section must not
// depend on any previous formatting
prevBreak := -1 // index of last expression that was followed by a linebreak
- linebreakMin := 1
- if mode&periodSep != 0 {
- // Make fragments like
- //
- // a.Bar(1,
- // 2).Foo
- //
- // format correctly (a linebreak shouldn't be added before Foo) when
- // doing period-separated expr lists by setting minimum linebreak to 0
- // lines for them.
- linebreakMin = 0
- }
- if prev.IsValid() && prev.Line < line && p.linebreak(line, linebreakMin, ws, true) {
+ if prev.IsValid() && prev.Line < line && p.linebreak(line, 0, ws, true) {
ws = ignore
*multiLine = true
prevBreak = 0
@@ -237,7 +225,7 @@
// lines are broken using newlines so comments remain aligned
// unless forceFF is set or there are multiple expressions on
// the same line in which case formfeed is used
- if p.linebreak(line, linebreakMin, ws, useFF || prevBreak+1 < i) {
+ if p.linebreak(line, 0, ws, useFF || prevBreak+1 < i) {
ws = ignore
*multiLine = true
prevBreak = i
diff --git a/src/pkg/go/printer/testdata/expressions.golden b/src/pkg/go/printer/testdata/expressions.golden
index 314d321..788b9cd 100644
--- a/src/pkg/go/printer/testdata/expressions.golden
+++ b/src/pkg/go/printer/testdata/expressions.golden
@@ -619,3 +619,13 @@
b.(T).
c
}
+
+
+// Don't introduce extra newlines in strangely formatted expression lists.
+func f() {
+ // os.Open parameters should remain on two lines
+ if writer, err = os.Open(outfile, s.O_WRONLY|os.O_CREATE|
+ os.O_TRUNC,0666); err != nil {
+ log.Fatal(err)
+ }
+}
diff --git a/src/pkg/go/printer/testdata/expressions.input b/src/pkg/go/printer/testdata/expressions.input
index cac22af..2c2ebce 100644
--- a/src/pkg/go/printer/testdata/expressions.input
+++ b/src/pkg/go/printer/testdata/expressions.input
@@ -625,3 +625,13 @@
(T).
c
}
+
+
+// Don't introduce extra newlines in strangely formatted expression lists.
+func f() {
+ // os.Open parameters should remain on two lines
+ if writer, err = os.Open(outfile, s.O_WRONLY|os.O_CREATE|
+ os.O_TRUNC, 0666); err != nil {
+ log.Fatal(err)
+ }
+}
diff --git a/src/pkg/go/printer/testdata/expressions.raw b/src/pkg/go/printer/testdata/expressions.raw
index f22ceeb..0d22779 100644
--- a/src/pkg/go/printer/testdata/expressions.raw
+++ b/src/pkg/go/printer/testdata/expressions.raw
@@ -618,3 +618,13 @@
b.(T).
c
}
+
+
+// Don't introduce extra newlines in strangely formatted expression lists.
+func f() {
+ // os.Open parameters should remain on two lines
+ if writer, err = os.Open(outfile, s.O_WRONLY|os.O_CREATE|
+ os.O_TRUNC,0666); err != nil {
+ log.Fatal(err)
+ }
+}
