all: single space after period.

The tree's pretty inconsistent about single space vs double space
after a period in documentation. Make it consistently a single space,
per earlier decisions. This means contributors won't be confused by
misleading precedence.

This CL doesn't use go/doc to parse. It only addresses // comments.
It was generated with:

$ perl -i -npe 's,^(\s*// .+[a-z]\.)  +([A-Z]),$1 $2,' $(git grep -l -E '^\s*//(.+\.)  +([A-Z])')
$ go test go/doc -update

Change-Id: Iccdb99c37c797ef1f804a94b22ba5ee4b500c4f7
Reviewed-on: https://go-review.googlesource.com/20022
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Dave Day <djd@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

7 files changed, 13 insertions, 13 deletions

diff --git a/src/sync/atomic/asm_arm.s b/src/sync/atomic/asm_arm.s
index 6cdc8fbc36..d35ea2a4e0 100644
--- a/src/sync/atomic/asm_arm.s
+++ b/src/sync/atomic/asm_arm.s
@@ -208,7 +208,7 @@ loop:
 ok:
 	RET
 
-// Fast, cached version of check.  No frame, just MOVW CMP RET after first time.
+// Fast, cached version of check. No frame, just MOVW CMP RET after first time.
 TEXT	fastCheck64<>(SB),NOSPLIT,$-4
 	MOVW	ok64<>(SB), R0
 	CMP	$0, R0	// have we been here before?
diff --git a/src/sync/atomic/atomic_test.go b/src/sync/atomic/atomic_test.go
index 23650abae9..deb3ccb55b 100644
--- a/src/sync/atomic/atomic_test.go
+++ b/src/sync/atomic/atomic_test.go
@@ -747,7 +747,7 @@ func TestStorePointer(t *testing.T) {
 // (Is the function atomic?)
 //
 // For each function, we write a "hammer" function that repeatedly
-// uses the atomic operation to add 1 to a value.  After running
+// uses the atomic operation to add 1 to a value. After running
 // multiple hammers in parallel, check that we end with the correct
 // total.
 // Swap can't add 1, so it uses a different scheme.
diff --git a/src/sync/cond.go b/src/sync/cond.go
index 0aefcda908..273884767f 100644
--- a/src/sync/cond.go
+++ b/src/sync/cond.go
@@ -35,13 +35,13 @@ func NewCond(l Locker) *Cond {
 }
 
 // Wait atomically unlocks c.L and suspends execution
-// of the calling goroutine.  After later resuming execution,
-// Wait locks c.L before returning.  Unlike in other systems,
+// of the calling goroutine. After later resuming execution,
+// Wait locks c.L before returning. Unlike in other systems,
 // Wait cannot return unless awoken by Broadcast or Signal.
 //
 // Because c.L is not locked when Wait first resumes, the caller
 // typically cannot assume that the condition is true when
-// Wait returns.  Instead, the caller should Wait in a loop:
+// Wait returns. Instead, the caller should Wait in a loop:
 //
 //    c.L.Lock()
 //    for !condition() {
diff --git a/src/sync/mutex.go b/src/sync/mutex.go
index eb526144c5..78b115cf5a 100644
--- a/src/sync/mutex.go
+++ b/src/sync/mutex.go
@@ -3,8 +3,8 @@
 // license that can be found in the LICENSE file.
 
 // Package sync provides basic synchronization primitives such as mutual
-// exclusion locks.  Other than the Once and WaitGroup types, most are intended
-// for use by low-level library routines.  Higher-level synchronization is
+// exclusion locks. Other than the Once and WaitGroup types, most are intended
+// for use by low-level library routines. Higher-level synchronization is
 // better done via channels and communication.
 //
 // Values containing the types defined in this package should not be copied.
diff --git a/src/sync/once.go b/src/sync/once.go
index 10b42fddc2..d8ef952ea5 100644
--- a/src/sync/once.go
+++ b/src/sync/once.go
@@ -18,10 +18,10 @@ type Once struct {
 // first time for this instance of Once. In other words, given
 // 	var once Once
 // if once.Do(f) is called multiple times, only the first call will invoke f,
-// even if f has a different value in each invocation.  A new instance of
+// even if f has a different value in each invocation. A new instance of
 // Once is required for each function to execute.
 //
-// Do is intended for initialization that must be run exactly once.  Since f
+// Do is intended for initialization that must be run exactly once. Since f
 // is niladic, it may be necessary to use a function literal to capture the
 // arguments to a function to be invoked by Do:
 // 	config.once.Do(func() { config.init(filename) })
diff --git a/src/sync/rwmutex.go b/src/sync/rwmutex.go
index d438c93c88..9fc6e3bd2c 100644
--- a/src/sync/rwmutex.go
+++ b/src/sync/rwmutex.go
@@ -94,11 +94,11 @@ func (rw *RWMutex) Lock() {
 	}
 }
 
-// Unlock unlocks rw for writing.  It is a run-time error if rw is
+// Unlock unlocks rw for writing. It is a run-time error if rw is
 // not locked for writing on entry to Unlock.
 //
 // As with Mutexes, a locked RWMutex is not associated with a particular
-// goroutine.  One goroutine may RLock (Lock) an RWMutex and then
+// goroutine. One goroutine may RLock (Lock) an RWMutex and then
 // arrange for another goroutine to RUnlock (Unlock) it.
 func (rw *RWMutex) Unlock() {
 	if race.Enabled {
diff --git a/src/sync/waitgroup.go b/src/sync/waitgroup.go
index c77fec306c..029e6077cd 100644
--- a/src/sync/waitgroup.go
+++ b/src/sync/waitgroup.go
@@ -12,8 +12,8 @@ import (
 
 // A WaitGroup waits for a collection of goroutines to finish.
 // The main goroutine calls Add to set the number of
-// goroutines to wait for.  Then each of the goroutines
-// runs and calls Done when finished.  At the same time,
+// goroutines to wait for. Then each of the goroutines
+// runs and calls Done when finished. At the same time,
 // Wait can be used to block until all goroutines have finished.
 type WaitGroup struct {
 	// 64-bit value: high 32 bits are counter, low 32 bits are waiter count.