Merge pull request #108 from buildpack/tar-timestamps

Normalize all tar file timestamps to Jan 01 1980 +1 second
buildpacks · Apr 1, 2019 · dc96f50 · dc96f50
2 parents 271f1f6 + f9d555e
commit dc96f50
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Showing 2 changed files with 12 additions and 12 deletions.
diff --git a/archive/tar.go b/archive/tar.go
@@ -57,7 +57,7 @@ func WriteTarArchive(w io.Writer, srcDir string, uid, gid int) error {
 			}
 		}
 		header.Name = file
-		header.ModTime = time.Time{}
+		header.ModTime = time.Date(1980, time.January, 1, 0, 0, 1, 0, time.UTC)
 		header.Uid = uid
 		header.Gid = gid
 		header.Uname = ""
@@ -99,7 +99,7 @@ func writeParentDirectoryHeaders(tarDir string, tw *tar.Writer, uid int, gid int
 			return err
 		}
 		header.Name = parent
-		header.ModTime = time.Time{}
+		header.ModTime = time.Date(1980, time.January, 1, 0, 0, 1, 0, time.UTC)
 
 		if err := tw.WriteHeader(header); err != nil {
 			return err

diff --git a/archive/tar_test.go b/archive/tar_test.go
@@ -67,12 +67,12 @@ func testTar(t *testing.T, when spec.G, it spec.S) {
 				header, err := tr.Next()
 				h.AssertNil(t, err)
 				h.AssertEq(t, header.Name, "testdata")
-				assertModTimeZeroedOut(t, header)
+				assertModTimeNormalized(t, header)
 
 				header, err = tr.Next()
 				h.AssertNil(t, err)
 				h.AssertEq(t, header.Name, "testdata/dir-to-tar")
-				assertModTimeZeroedOut(t, header)
+				assertModTimeNormalized(t, header)
 			})
 
 			tarContains(t, "regular files", func() {
@@ -85,14 +85,14 @@ func testTar(t *testing.T, when spec.G, it spec.S) {
 				h.AssertEq(t, string(fileContents), "some-content")
 				h.AssertEq(t, header.Uid, uid)
 				h.AssertEq(t, header.Gid, gid)
-				assertModTimeZeroedOut(t, header)
+				assertModTimeNormalized(t, header)
 			})
 
 			tarContains(t, "sub directories", func() {
 				header, err := tr.Next()
 				h.AssertNil(t, err)
 				h.AssertEq(t, header.Name, "testdata/dir-to-tar/sub-dir")
-				assertModTimeZeroedOut(t, header)
+				assertModTimeNormalized(t, header)
 			})
 
 			tarContains(t, "symlinks", func() {
@@ -103,7 +103,7 @@ func testTar(t *testing.T, when spec.G, it spec.S) {
 				h.AssertEq(t, header.Uid, uid)
 				h.AssertEq(t, header.Gid, gid)
 				h.AssertEq(t, header.Linkname, "../some-file.txt")
-				assertModTimeZeroedOut(t, header)
+				assertModTimeNormalized(t, header)
 			})
 		})
 
@@ -132,7 +132,7 @@ func testTar(t *testing.T, when spec.G, it spec.S) {
 					h.AssertEq(t, header.Name, expectedDir)
 
 					assertDirectory(t, header)
-					assertModTimeZeroedOut(t, header)
+					assertModTimeNormalized(t, header)
 				}
 			})
 		})
@@ -161,7 +161,7 @@ func testTar(t *testing.T, when spec.G, it spec.S) {
 					h.AssertEq(t, header.Name, expectedDir)
 
 					assertDirectory(t, header)
-					assertModTimeZeroedOut(t, header)
+					assertModTimeNormalized(t, header)
 
 				}
 			})
@@ -221,10 +221,10 @@ func assertDirectory(t *testing.T, header *tar.Header) {
 	}
 }
 
-func assertModTimeZeroedOut(t *testing.T, header *tar.Header) {
+func assertModTimeNormalized(t *testing.T, header *tar.Header) {
 	t.Helper()
-	if header.ModTime.Unix() != 0 {
-		t.Fatalf(`expected %s time not to be set instead: %s`, header.Name, header.ModTime.String())
+	if !header.ModTime.Equal(time.Date(1980, time.January, 1, 0, 0, 1, 0, time.UTC)) {
+		t.Fatalf(`expected %s time to be normalized, instead got: %s`, header.Name, header.ModTime.String())
 	}
 }