fix: handle builds with trimpath enabled (#120)

Co-authored-by: Andre Klärner <kandre+github@ak-online.be>

.github/workflows/go.yml

@@ -49,3 +49,5 @@ jobs:
           go-version: 1.21.x
       - name: Run Tests
         run: make test
+      - name: Run Tests
+        run: make test-trimpath

Makefile

@@ -20,3 +20,6 @@ test: ## Run tests
 
 test-verbose: ## Run tests with verbose output
 	go test -race -count=10 -shuffle on -v -cover ./...
+
+test-trimpath: ## Run tests with -trimpath
+	GOFLAGS=-trimpath go test -race -count=10 -shuffle on -v -cover ./examples

README.md

@@ -34,9 +34,9 @@
 - [Running tests on CI](#running-tests-on-ci)
 - [No Color](#no-color)
 - [Snapshots Structure](#snapshots-structure)
+- [Known Limitations](#known-limitations)
 - [Acknowledgments](#acknowledgments)
 - [Contributing](./contributing.md)
-- [Appendix](#appendix)
 
 ## Installation
 
@@ -411,21 +411,16 @@ map[string]interface{}{
 > [!NOTE]
 > If your snapshot data contain characters `---` at the start of a line followed by a new line, `go-snaps` will "escape" them and save them as `/-/-/-/` to differentiate them from termination characters.
 
+## Known Limitations
+
+- When running a specific test file by specifying a path `go test ./my_test.go`, `go-snaps` can't track the path so it will mistakenly mark snapshots as obsolete.
+- go-snaps doesn't handle CRLF line endings. If you are using Windows, you may need to convert the line endings to LF.
+- go-snaps cannot determine the snapshot path automatically when running with `go test -trimpath ./...`. It then instead relies on the current working directory to define the snapshot directory. If this is a problem in your use case you can set an absolute path with `snaps.WithConfig(snaps.Dir("/some/absolute/path"))`
+
 ## Acknowledgments
 
 This library used [Jest Snapshoting](https://jestjs.io/docs/snapshot-testing) and [Cupaloy](https://github.com/bradleyjkemp/cupaloy) as inspiration.
 
 - Jest is a full-fledged Javascript testing framework and has robust snapshoting features.
 - Cupaloy is a great and simple Golang snapshoting solution.
 - The [logo](https://github.com/MariaLetta/free-gophers-pack) was made by [MariaLetta](https://github.com/MariaLetta).
-
-## Appendix
-
-> [!WARNING]
-> When running a specific test file by specifying a path `go test ./my_test.go`, `go-snaps` can't track the path so it will mistakenly mark snapshots as obsolete.
-
-> [!IMPORTANT]
-> Snapshots should be treated as code. The snapshot artifact should be committed alongside code changes, and reviewed as part of your code review process
-
-> [!NOTE]
-> go-snaps doesn't handle CRLF line endings. If you are using Windows, you may need to convert the line endings to LF.

examples/matchSnapshot_test.go

@@ -5,8 +5,6 @@ import (
 	"flag"
 	"fmt"
 	"os"
-	"path/filepath"
-	"runtime"
 	"testing"
 
 	"github.com/gkampitakis/go-snaps/snaps"
@@ -80,10 +78,9 @@ func TestMatchSnapshot(t *testing.T) {
 		})
 
 		t.Run("should allow absolute path", func(t *testing.T) {
-			_, b, _, _ := runtime.Caller(0)
-			basepath := filepath.Dir(b)
+			dir, _ := os.Getwd()
 
-			snaps.WithConfig(snaps.Dir(basepath+"/absolute_path")).
+			snaps.WithConfig(snaps.Dir(dir+"/absolute_path")).
 				MatchSnapshot(t, "supporting absolute path")
 		})
 

snaps/snapshot.go

@@ -318,12 +318,15 @@ func snapshotPath(c *Config, tName string, isStandalone bool) (string, string) {
 	callerFilename := baseCaller(3)
 
 	dir := c.snapsDir
-	if !filepath.IsAbs(dir) {
+	if !filepath.IsAbs(dir) && !isTrimBathBuild {
 		dir = filepath.Join(filepath.Dir(callerFilename), c.snapsDir)
 	}
 
 	snapPath := filepath.Join(dir, constructFilename(c, callerFilename, tName, isStandalone))
-	snapPathRel, _ := filepath.Rel(filepath.Dir(callerFilename), snapPath)
+	snapPathRel := snapPath
+	if !isTrimBathBuild {
+		snapPathRel, _ = filepath.Rel(filepath.Dir(callerFilename), snapPath)
+	}
 
 	return snapPath, snapPathRel
 }

snaps/utils.go

@@ -8,6 +8,8 @@ import (
 	"os"
 	"path/filepath"
 	"runtime"
+	"runtime/debug"
+	"slices"
 	"strings"
 	"sync"
 
@@ -22,6 +24,7 @@ var (
 	defaultConfig   = Config{
 		snapsDir: "__snapshots__",
 	}
+	isTrimBathBuild = trimPathBuild()
 )
 
 const (
@@ -138,3 +141,26 @@ func shouldCreate(u *bool) bool {
 
 	return true
 }
+
+// trimPathBuild checks if the build has trimpath setting true
+func trimPathBuild() bool {
+	keys := []string{"-trimpath", "--trimpath"}
+	goFlags := strings.Split(os.Getenv("GOFLAGS"), " ")
+
+	for _, flag := range goFlags {
+		if slices.Contains(keys, flag) {
+			return true
+		}
+	}
+
+	bInfo, ok := debug.ReadBuildInfo()
+	if ok && len(bInfo.Settings) > 0 {
+		for _, info := range bInfo.Settings {
+			if slices.Contains(keys, info.Key) {
+				return info.Value == "true"
+			}
+		}
+	}
+
+	return runtime.GOROOT() == ""
+}