compiler_wrapper: Fix findings from staticcheck

This CL fixes the following staticcheck findings:

clang_tidy_flag.go:235:6: func hasAtLeastOneSuffix is unused (U1000)
command.go:96:13: error strings should not be capitalized (ST1005)
compiler_wrapper.go:97:22: should use time.Since instead of time.Now().Sub (S1012)
compiler_wrapper.go:154:3: this value of cSrcFile is never used (SA4006)
compiler_wrapper.go:187:12: unnecessary use of fmt.Sprintf (S1039)
env.go:148:5: var _env is unused (U1000)
env_test.go:228:2: this value of err is never used (SA4006)
iwyu_flag.go:18:7: const iwyuCrashSubstring is unused (U1000)

BUG=b:295930281
TEST=go test

Change-Id: I3d365243192f9041d12b9c8385d4bd8ff1bd5669
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/4779192
Reviewed-by: George Burgess <gbiv@chromium.org>
Commit-Queue: Ryan Beltran <ryanbeltran@chromium.org>
Tested-by: Ryan Beltran <ryanbeltran@chromium.org>

7 files changed, 8 insertions, 17 deletions

diff --git a/compiler_wrapper/clang_tidy_flag.go b/compiler_wrapper/clang_tidy_flag.go
index e3940825..9722b39e 100644
--- a/compiler_wrapper/clang_tidy_flag.go
+++ b/compiler_wrapper/clang_tidy_flag.go
@@ -231,12 +231,3 @@ func runClangTidy(env env, clangCmd *command, cSrcFile string, extraTidyFlags []
 	}
 	return err
 }
-
-func hasAtLeastOneSuffix(s string, suffixes []string) bool {
-	for _, suffix := range suffixes {
-		if strings.HasSuffix(s, suffix) {
-			return true
-		}
-	}
-	return false
-}
diff --git a/compiler_wrapper/command.go b/compiler_wrapper/command.go
index e2a5176d..d19c903a 100644
--- a/compiler_wrapper/command.go
+++ b/compiler_wrapper/command.go
@@ -93,7 +93,7 @@ func resolveAgainstPathEnv(env env, cmd string) (string, error) {
 			return resolvedPath, nil
 		}
 	}
-	return "", fmt.Errorf("Couldn't find cmd %q in path", cmd)
+	return "", fmt.Errorf("couldn't find cmd %q in path", cmd)
 }
 
 func getAbsCmdPath(env env, cmd *command) string {
diff --git a/compiler_wrapper/compiler_wrapper.go b/compiler_wrapper/compiler_wrapper.go
index a299698c..bb144881 100644
--- a/compiler_wrapper/compiler_wrapper.go
+++ b/compiler_wrapper/compiler_wrapper.go
@@ -94,7 +94,7 @@ func runAndroidClangTidy(env env, cmd *command) error {
 	if !errors.Is(err, context.DeadlineExceeded) {
 		// When used time is over half of TIDY_TIMEOUT, give a warning.
 		// These warnings allow users to fix slow jobs before they get worse.
-		usedSeconds := int(time.Now().Sub(startTime) / time.Second)
+		usedSeconds := int(time.Since(startTime) / time.Second)
 		if usedSeconds > seconds/2 {
 			warning := "%s:1:1: warning: clang-tidy used %d seconds.\n"
 			fmt.Fprintf(env.stdout(), warning, getSourceFile(), usedSeconds)
@@ -151,7 +151,7 @@ func callCompilerInternal(env env, cfg *config, inputCmd *command) (exitCode int
 			return 0, newErrorwithSourceLocf("unsupported compiler: %s", mainBuilder.target.compiler)
 		}
 	} else {
-		cSrcFile, tidyFlags, tidyMode := processClangTidyFlags(mainBuilder)
+		_, tidyFlags, tidyMode := processClangTidyFlags(mainBuilder)
 		cSrcFile, iwyuFlags, iwyuMode := processIWYUFlags(mainBuilder)
 		if mainBuilder.target.compilerType == clangType {
 			err := prepareClangCommand(mainBuilder)
@@ -184,7 +184,7 @@ func callCompilerInternal(env env, cfg *config, inputCmd *command) (exitCode int
 
 			if iwyuMode != iwyuModeNone {
 				if iwyuMode == iwyuModeError {
-					panic(fmt.Sprintf("Unknown IWYU mode"))
+					panic("Unknown IWYU mode")
 				}
 
 				allowCCache = false
diff --git a/compiler_wrapper/env.go b/compiler_wrapper/env.go
index 2dad6115..38f07cab 100644
--- a/compiler_wrapper/env.go
+++ b/compiler_wrapper/env.go
@@ -145,7 +145,7 @@ type printingEnv struct {
 	env
 }
 
-var _env = (*printingEnv)(nil)
+var _ env = (*printingEnv)(nil)
 
 func (env *printingEnv) exec(cmd *command) error {
 	printCmd(env, cmd)
diff --git a/compiler_wrapper/env_test.go b/compiler_wrapper/env_test.go
index 6b00a8b5..c10942de 100644
--- a/compiler_wrapper/env_test.go
+++ b/compiler_wrapper/env_test.go
@@ -226,6 +226,9 @@ func TestNewProcessEnvResolvesPwdAwayProperly(t *testing.T) {
 	os.Unsetenv(envPwd)
 
 	initialWd, err := os.Getwd()
+	if err != nil {
+		t.Fatalf("Failed getting working directory: %v", err)
+	}
 	if initialWd == "/proc/self/cwd" {
 		t.Fatalf("Working directory should never be %q when env is unset", initialWd)
 	}
diff --git a/compiler_wrapper/iwyu_flag.go b/compiler_wrapper/iwyu_flag.go
index 6194bf40..5788d8c7 100644
--- a/compiler_wrapper/iwyu_flag.go
+++ b/compiler_wrapper/iwyu_flag.go
@@ -15,8 +15,6 @@ import (
 
 type useIWYUMode int
 
-const iwyuCrashSubstring = "PLEASE submit a bug report"
-
 const (
 	iwyuModeNone useIWYUMode = iota
 	iwyuModeAll
diff --git a/compiler_wrapper/testutil_test.go b/compiler_wrapper/testutil_test.go
index 74e05a63..8bac479b 100644
--- a/compiler_wrapper/testutil_test.go
+++ b/compiler_wrapper/testutil_test.go
@@ -39,7 +39,6 @@ type testContext struct {
 	tempDir      string
 	env          []string
 	cfg          *config
-	inputCmd     *command
 	lastCmd      *command
 	cmdCount     int
 	cmdMock      func(cmd *command, stdin io.Reader, stdout io.Writer, stderr io.Writer) error