internal/cmd: print generated filename only when contents change
Printing the filenames of regenerated files only when the contents
change makes it easier to tell when a change has produced the expected
result in the generated file output.
Change-Id: I74d0020be1de3d287bb8400ba290131008859bf1
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/220356
Reviewed-by: Joe Tsai <joetsai@google.com>
diff --git a/internal/cmd/generate-protos/main.go b/internal/cmd/generate-protos/main.go
index 00dc876..c217e66 100644
--- a/internal/cmd/generate-protos/main.go
+++ b/internal/cmd/generate-protos/main.go
@@ -7,6 +7,7 @@
package main
import (
+ "bytes"
"flag"
"fmt"
"go/format"
@@ -304,8 +305,9 @@
dstPath := filepath.Join(dstDir, relPath)
if run {
- fmt.Println("#", relPath)
- copyFile(dstPath, srcPath)
+ if copyFile(dstPath, srcPath) {
+ fmt.Println("#", relPath)
+ }
} else {
cmd := exec.Command("diff", dstPath, srcPath, "-N", "-u")
cmd.Stdout = os.Stdout
@@ -315,11 +317,16 @@
})
}
-func copyFile(dstPath, srcPath string) {
- b, err := ioutil.ReadFile(srcPath)
+func copyFile(dstPath, srcPath string) (changed bool) {
+ src, err := ioutil.ReadFile(srcPath)
check(err)
check(os.MkdirAll(filepath.Dir(dstPath), 0775))
- check(ioutil.WriteFile(dstPath, b, 0664))
+ dst, _ := ioutil.ReadFile(dstPath)
+ if bytes.Equal(src, dst) {
+ return false
+ }
+ check(ioutil.WriteFile(dstPath, src, 0664))
+ return true
}
func protoMapOpt() string {
diff --git a/internal/cmd/generate-types/main.go b/internal/cmd/generate-types/main.go
index 62e147a..bf1da2b 100644
--- a/internal/cmd/generate-types/main.go
+++ b/internal/cmd/generate-types/main.go
@@ -226,8 +226,11 @@
absFile := filepath.Join(repoRoot, file)
if run {
- fmt.Println("#", file)
- check(ioutil.WriteFile(absFile, b, 0664))
+ prev, _ := ioutil.ReadFile(absFile)
+ if !bytes.Equal(b, prev) {
+ fmt.Println("#", file)
+ check(ioutil.WriteFile(absFile, b, 0664))
+ }
} else {
check(ioutil.WriteFile(absFile+".tmp", b, 0664))
defer os.Remove(absFile + ".tmp")
