From 7c72e04c68692ff197c4b14b6f2a5ac02c09ec17 Mon Sep 17 00:00:00 2001
From: Prashant V <prashant@prashantv.com>
Date: Wed, 22 May 2024 23:15:49 -0700
Subject: [PATCH] toolexec_test: extract out tracePaths

This is a prefactor for testing unsafe rewrites, where there can be
additional traces depending on what packages are enabled for unsafe
rewrites. These additional traces can be marked with different markers
so allow finding trace lines for any marker.
---
 cmd/errtrace/toolexec_test.go | 66 +++++++++++++++++++----------------
 1 file changed, 36 insertions(+), 30 deletions(-)

diff --git a/cmd/errtrace/toolexec_test.go b/cmd/errtrace/toolexec_test.go
index aaa8c8c..9cf64b9 100644
--- a/cmd/errtrace/toolexec_test.go
+++ b/cmd/errtrace/toolexec_test.go
@@ -32,34 +32,7 @@ func TestToolExec(t *testing.T) {
 		t.Fatalf("compile errtrace failed: %v\nstderr: %s", err, stderr)
 	}
 
-	var wantTraces []string
-	err = filepath.Walk(testProgDir, func(path string, info fs.FileInfo, err error) error {
-		if err != nil {
-			return errtrace.Wrap(err)
-		}
-		if info.IsDir() {
-			return nil
-		}
-
-		for _, line := range findTraceLines(t, path) {
-			absPath, err := filepath.Abs(path)
-			if err != nil {
-				t.Fatalf("abspath: %v", err)
-			}
-			if runtime.GOOS == "windows" {
-				// On Windows, absPath uses windows path separators, e.g., "c:\foo"
-				// but the paths reported in traces contain '/'.
-				absPath = filepath.ToSlash(absPath)
-			}
-
-			wantTraces = append(wantTraces, fmt.Sprintf("%v:%v", absPath, line))
-		}
-		return nil
-	})
-	if err != nil {
-		t.Fatal("Walk failed", err)
-	}
-	sort.Strings(wantTraces)
+	wantTraces := tracePaths(t, testProgDir, "@trace")
 
 	tests := []struct {
 		name       string
@@ -181,7 +154,40 @@ func TestToolExec(t *testing.T) {
 	}
 }
 
-func findTraceLines(t testing.TB, file string) []int {
+func tracePaths(t testing.TB, path string, traceMarker string) []string {
+	var wantTraces []string
+	err := filepath.Walk(path, func(path string, info fs.FileInfo, err error) error {
+		if err != nil {
+			return errtrace.Wrap(err)
+		}
+		if info.IsDir() {
+			return nil
+		}
+
+		for _, line := range findTraceLines(t, path, traceMarker) {
+			absPath, err := filepath.Abs(path)
+			if err != nil {
+				t.Fatalf("abspath: %v", err)
+			}
+			if runtime.GOOS == "windows" {
+				// On Windows, absPath uses windows path separators, e.g., "c:\foo"
+				// but the paths reported in traces contain '/'.
+				absPath = filepath.ToSlash(absPath)
+			}
+
+			wantTraces = append(wantTraces, fmt.Sprintf("%v:%v", absPath, line))
+		}
+		return nil
+	})
+	if err != nil {
+		t.Fatalf("tracePaths failed: %v", err)
+	}
+
+	sort.Strings(wantTraces)
+	return wantTraces
+}
+
+func findTraceLines(t testing.TB, file string, traceMarker string) []int {
 	f, err := os.Open(file)
 	if err != nil {
 		t.Fatal(err)
@@ -194,7 +200,7 @@ func findTraceLines(t testing.TB, file string) []int {
 	for scanner.Scan() {
 		lineNum++
 		line := scanner.Text()
-		if strings.Contains(line, "// @trace") {
+		if strings.Contains(line, "// "+traceMarker) {
 			traces = append(traces, lineNum)
 		}
 	}