[release-branch.go1.2] time: correct path to time zone zip file on Unix

??? CL 19280043 / 9d199c7582d6
time: correct path to time zone zip file on Unix

Most Unix systems have their own time zone data,
so we almost never get far enough in the list to
discover that we cannot fall back to the zip file.
Adjust testing to exercise the final fallback.

Plan 9 and Windows were already correct
(and are the main users of the zip file).

R=golang-dev, bradfitz
CC=golang-dev
https://codereview.appspot.com/19280043
???

R=golang-dev
CC=golang-dev
https://codereview.appspot.com/20640043

5 files changed, 35 insertions, 2 deletions

diff --git a/src/pkg/time/export_test.go b/src/pkg/time/export_test.go
index dbd553af4..6cd535f6b 100644
--- a/src/pkg/time/export_test.go
+++ b/src/pkg/time/export_test.go
@@ -18,4 +18,7 @@ func ForceUSPacificForTesting() {
 	localOnce.Do(initTestingZone)
 }
 
-var ParseTimeZone = parseTimeZone
+var (
+	ForceZipFileForTesting = forceZipFileForTesting
+	ParseTimeZone          = parseTimeZone
+)
diff --git a/src/pkg/time/time_test.go b/src/pkg/time/time_test.go
index 22b751c52..334c4b0cf 100644
--- a/src/pkg/time/time_test.go
+++ b/src/pkg/time/time_test.go
@@ -578,6 +578,16 @@ func TestParseInSydney(t *testing.T) {
 	}
 }
 
+func TestLoadLocationZipFile(t *testing.T) {
+	ForceZipFileForTesting(true)
+	defer ForceZipFileForTesting(false)
+
+	_, err := LoadLocation("Australia/Sydney")
+	if err != nil {
+		t.Fatal(err)
+	}
+}
+
 var rubyTests = []ParseTest{
 	{"RubyDate", RubyDate, "Thu Feb 04 21:00:57 -0800 2010", true, true, 1, 0},
 	// Ignore the time zone in the test. If it parses, it'll be OK.
diff --git a/src/pkg/time/zoneinfo_plan9.go b/src/pkg/time/zoneinfo_plan9.go
index 6855238dc..0e8f3811b 100644
--- a/src/pkg/time/zoneinfo_plan9.go
+++ b/src/pkg/time/zoneinfo_plan9.go
@@ -154,3 +154,7 @@ func loadLocation(name string) (*Location, error) {
 	}
 	return nil, errors.New("unknown time zone " + name)
 }
+
+func forceZipFileForTesting(zipOnly bool) {
+	// We only use the zip file anyway.
+}
diff --git a/src/pkg/time/zoneinfo_unix.go b/src/pkg/time/zoneinfo_unix.go
index 53b5dc82c..fc5ae89fe 100644
--- a/src/pkg/time/zoneinfo_unix.go
+++ b/src/pkg/time/zoneinfo_unix.go
@@ -32,7 +32,19 @@ var zoneDirs = []string{
 	"/usr/share/zoneinfo/",
 	"/usr/share/lib/zoneinfo/",
 	"/usr/lib/locale/TZ/",
-	runtime.GOROOT() + "/lib/time/zoneinfo/",
+	runtime.GOROOT() + "/lib/time/zoneinfo.zip",
+}
+
+var origZoneDirs = zoneDirs
+
+func forceZipFileForTesting(zipOnly bool) {
+	zoneDirs = make([]string, len(origZoneDirs))
+	copy(zoneDirs, origZoneDirs)
+	if zipOnly {
+		for i := 0; i < len(zoneDirs)-1; i++ {
+			zoneDirs[i] = "/XXXNOEXIST"
+		}
+	}
 }
 
 func initLocal() {
diff --git a/src/pkg/time/zoneinfo_windows.go b/src/pkg/time/zoneinfo_windows.go
index 1e18ad295..be4e5c13f 100644
--- a/src/pkg/time/zoneinfo_windows.go
+++ b/src/pkg/time/zoneinfo_windows.go
@@ -264,3 +264,7 @@ func loadLocation(name string) (*Location, error) {
 	}
 	return nil, errors.New("unknown time zone " + name)
 }
+
+func forceZipFileForTesting(zipOnly bool) {
+	// We only use the zip file anyway.
+}