Merge 15ef1d4739f1c7765bc3c6979040a584853786e2 into d1a15347b1e45a8ee816193d3578a93bfd73b70f

Co-authored-by: Bo-Yi Wu <appleboy.tw@gmail.com>

context.go

@@ -55,14 +55,6 @@ const ContextRequestKey ContextKeyType = 0
 // abortIndex represents a typical value used in abort functions.
 const abortIndex int8 = math.MaxInt8 >> 1
 
-// safeInt8 converts int to int8 safely, capping at math.MaxInt8
-func safeInt8(n int) int8 {
-	if n > math.MaxInt8 {
-		return math.MaxInt8
-	}
-	return int8(n)
-}
-
 // Context is the most important part of gin. It allows us to pass variables between middleware,
 // manage the flow, validate the JSON of a request and render a JSON response for example.
 type Context struct {

context_test.go

@@ -20,6 +20,7 @@ import (
 	"os"
 	"path/filepath"
 	"reflect"
+	"runtime"
 	"strconv"
 	"strings"
 	"sync"
@@ -75,6 +76,285 @@ func must(err error) {
 	}
 }
 
+// TestContextNegotiate tests the Context.Negotiate() method
+func TestContextNegotiate(t *testing.T) {
+	// Test JSON negotiation
+	t.Run("negotiate JSON", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		c, _ := CreateTestContext(w)
+		c.Request = httptest.NewRequest(http.MethodGet, "/test", nil)
+		c.Request.Header.Set("Accept", "application/json")
+
+		data := map[string]string{"message": "hello"}
+		c.Negotiate(http.StatusOK, Negotiate{
+			Offered:  []string{binding.MIMEJSON, binding.MIMEHTML},
+			JSONData: data,
+			HTMLName: "test.html",
+			HTMLData: data,
+		})
+
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Contains(t, w.Header().Get("Content-Type"), "application/json")
+		assert.Contains(t, w.Body.String(), `"message":"hello"`)
+	})
+
+	// Test HTML negotiation
+	t.Run("negotiate HTML", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		c, engine := CreateTestContext(w)
+		c.Request = httptest.NewRequest(http.MethodGet, "/test", nil)
+		c.Request.Header.Set("Accept", "text/html")
+
+		// Set up a simple HTML template
+		tmpl := template.Must(template.New("test").Parse(`<h1>{{.message}}</h1>`))
+		engine.SetHTMLTemplate(tmpl)
+
+		data := map[string]string{"message": "hello"}
+		c.Negotiate(http.StatusOK, Negotiate{
+			Offered:  []string{binding.MIMEJSON, binding.MIMEHTML},
+			JSONData: data,
+			HTMLName: "test",
+			HTMLData: data,
+		})
+
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Contains(t, w.Header().Get("Content-Type"), "text/html")
+		assert.Contains(t, w.Body.String(), "<h1>hello</h1>")
+	})
+
+	// Test XML negotiation
+	t.Run("negotiate XML", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		c, _ := CreateTestContext(w)
+		c.Request = httptest.NewRequest(http.MethodGet, "/test", nil)
+		c.Request.Header.Set("Accept", "application/xml")
+
+		type TestData struct {
+			Message string `xml:"message"`
+		}
+		data := TestData{Message: "hello"}
+
+		c.Negotiate(http.StatusOK, Negotiate{
+			Offered: []string{binding.MIMEJSON, binding.MIMEXML},
+			XMLData: data,
+		})
+
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Contains(t, w.Header().Get("Content-Type"), "application/xml")
+		assert.Contains(t, w.Body.String(), "<message>hello</message>")
+	})
+
+	// Test YAML negotiation
+	t.Run("negotiate YAML", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		c, _ := CreateTestContext(w)
+		c.Request = httptest.NewRequest(http.MethodGet, "/test", nil)
+		c.Request.Header.Set("Accept", "application/x-yaml")
+
+		data := map[string]string{"message": "hello"}
+		c.Negotiate(http.StatusOK, Negotiate{
+			Offered:  []string{binding.MIMEJSON, binding.MIMEYAML},
+			YAMLData: data,
+		})
+
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Contains(t, w.Header().Get("Content-Type"), "application/yaml")
+		assert.Contains(t, w.Body.String(), "message: hello")
+	})
+
+	// Test TOML negotiation
+	t.Run("negotiate TOML", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		c, _ := CreateTestContext(w)
+		c.Request = httptest.NewRequest(http.MethodGet, "/test", nil)
+		c.Request.Header.Set("Accept", "application/toml")
+
+		data := map[string]string{"message": "hello"}
+		c.Negotiate(http.StatusOK, Negotiate{
+			Offered:  []string{binding.MIMEJSON, binding.MIMETOML},
+			TOMLData: data,
+		})
+
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Contains(t, w.Header().Get("Content-Type"), "application/toml")
+		assert.Contains(t, w.Body.String(), `message = 'hello'`)
+	})
+
+	// Test fallback to Data field
+	t.Run("fallback to Data field", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		c, _ := CreateTestContext(w)
+		c.Request = httptest.NewRequest(http.MethodGet, "/test", nil)
+		c.Request.Header.Set("Accept", "application/json")
+
+		data := map[string]string{"message": "hello"}
+		c.Negotiate(http.StatusOK, Negotiate{
+			Offered: []string{binding.MIMEJSON},
+			Data:    data, // No JSONData, should fallback to Data
+		})
+
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Contains(t, w.Header().Get("Content-Type"), "application/json")
+		assert.Contains(t, w.Body.String(), `"message":"hello"`)
+	})
+
+	// Test specific data takes precedence over Data field
+	t.Run("specific data takes precedence", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		c, _ := CreateTestContext(w)
+		c.Request = httptest.NewRequest(http.MethodGet, "/test", nil)
+		c.Request.Header.Set("Accept", "application/json")
+
+		jsonData := map[string]string{"type": "json"}
+		fallbackData := map[string]string{"type": "fallback"}
+
+		c.Negotiate(http.StatusOK, Negotiate{
+			Offered:  []string{binding.MIMEJSON},
+			JSONData: jsonData,
+			Data:     fallbackData,
+		})
+
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Contains(t, w.Body.String(), `"type":"json"`)
+		assert.NotContains(t, w.Body.String(), `"type":"fallback"`)
+	})
+
+	// Test multiple Accept headers with quality values
+	t.Run("multiple Accept headers with quality", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		c, _ := CreateTestContext(w)
+		c.Request = httptest.NewRequest(http.MethodGet, "/test", nil)
+		c.Request.Header.Set("Accept", "application/xml;q=0.9, application/json;q=1.0")
+
+		data := map[string]string{"message": "hello"}
+		c.Negotiate(http.StatusOK, Negotiate{
+			Offered:  []string{binding.MIMEXML, binding.MIMEJSON},
+			JSONData: data,
+			XMLData:  data,
+		})
+
+		// Should choose XML as it appears first in the Offered slice
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Contains(t, w.Header().Get("Content-Type"), "application/xml")
+	})
+
+	// Test wildcard Accept header
+	t.Run("wildcard Accept header", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		c, _ := CreateTestContext(w)
+		c.Request = httptest.NewRequest(http.MethodGet, "/test", nil)
+		c.Request.Header.Set("Accept", "*/*")
+
+		data := map[string]string{"message": "hello"}
+		c.Negotiate(http.StatusOK, Negotiate{
+			Offered:  []string{binding.MIMEJSON, binding.MIMEXML},
+			JSONData: data,
+		})
+
+		// Should choose the first offered format
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Contains(t, w.Header().Get("Content-Type"), "application/json")
+	})
+
+	// Test no Accept header (should default to first offered)
+	t.Run("no Accept header", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		c, _ := CreateTestContext(w)
+		c.Request = httptest.NewRequest(http.MethodGet, "/test", nil)
+		// No Accept header set
+
+		data := map[string]string{"message": "hello"}
+		c.Negotiate(http.StatusOK, Negotiate{
+			Offered:  []string{binding.MIMEXML, binding.MIMEJSON},
+			XMLData:  data,
+			JSONData: data,
+		})
+
+		// Should choose the first offered format (XML)
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Contains(t, w.Header().Get("Content-Type"), "application/xml")
+	})
+
+	// Test unsupported Accept header
+	t.Run("unsupported Accept header", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		c, _ := CreateTestContext(w)
+		c.Request = httptest.NewRequest(http.MethodGet, "/test", nil)
+		c.Request.Header.Set("Accept", "application/pdf")
+
+		data := map[string]string{"message": "hello"}
+		c.Negotiate(http.StatusOK, Negotiate{
+			Offered:  []string{binding.MIMEJSON, binding.MIMEXML},
+			JSONData: data,
+		})
+
+		// Should return 406 Not Acceptable
+		assert.Equal(t, http.StatusNotAcceptable, w.Code)
+		assert.True(t, c.IsAborted())
+	})
+
+	// Test partial match in Accept header
+	t.Run("partial match in Accept header", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		c, engine := CreateTestContext(w)
+		c.Request = httptest.NewRequest(http.MethodGet, "/test", nil)
+		c.Request.Header.Set("Accept", "text/*")
+
+		// Set up a simple HTML template
+		tmpl := template.Must(template.New("test").Parse(`<h1>{{.message}}</h1>`))
+		engine.SetHTMLTemplate(tmpl)
+
+		data := map[string]string{"message": "hello"}
+		c.Negotiate(http.StatusOK, Negotiate{
+			Offered:  []string{binding.MIMEJSON, binding.MIMEHTML},
+			JSONData: data,
+			HTMLName: "test",
+			HTMLData: data,
+		})
+
+		// Should match text/html
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Contains(t, w.Header().Get("Content-Type"), "text/html")
+	})
+
+	// Test YAML2 MIME type
+	t.Run("negotiate YAML2 MIME type", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		c, _ := CreateTestContext(w)
+		c.Request = httptest.NewRequest(http.MethodGet, "/test", nil)
+		c.Request.Header.Set("Accept", "application/yaml")
+
+		data := map[string]string{"message": "hello"}
+		c.Negotiate(http.StatusOK, Negotiate{
+			Offered:  []string{binding.MIMEJSON, binding.MIMEYAML2},
+			YAMLData: data,
+		})
+
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Contains(t, w.Header().Get("Content-Type"), "application/yaml")
+		assert.Contains(t, w.Body.String(), "message: hello")
+	})
+
+	// Test complex Accept header with multiple types and quality values
+	t.Run("complex Accept header", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		c, _ := CreateTestContext(w)
+		c.Request = httptest.NewRequest(http.MethodGet, "/test", nil)
+		c.Request.Header.Set("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8")
+
+		data := map[string]string{"message": "hello"}
+		c.Negotiate(http.StatusOK, Negotiate{
+			Offered:  []string{binding.MIMEXML, binding.MIMEJSON},
+			XMLData:  data,
+			JSONData: data,
+		})
+
+		// Should choose XML as it's explicitly mentioned in Accept header
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Contains(t, w.Header().Get("Content-Type"), "application/xml")
+	})
+}
+
 // TestContextFile tests the Context.File() method
 func TestContextFile(t *testing.T) {
 	// Test serving an existing file
@@ -179,6 +459,20 @@ func TestContextFormFileFailed(t *testing.T) {
 	assert.Nil(t, f)
 }
 
+func TestContextFormFileParseMultipartFormFailed(t *testing.T) {
+	c, _ := CreateTestContext(httptest.NewRecorder())
+	// Create a request with invalid multipart form data
+	body := strings.NewReader("invalid multipart data")
+	c.Request, _ = http.NewRequest(http.MethodPost, "/", body)
+	c.Request.Header.Set("Content-Type", "multipart/form-data; boundary=invalid")
+	c.engine.MaxMultipartMemory = 8 << 20
+
+	// This should trigger the error handling in FormFile when ParseMultipartForm fails
+	f, err := c.FormFile("file")
+	require.Error(t, err)
+	assert.Nil(t, f)
+}
+
 func TestContextMultipartForm(t *testing.T) {
 	buf := new(bytes.Buffer)
 	mw := multipart.NewWriter(buf)
@@ -273,6 +567,43 @@ func TestSaveUploadedFileWithPermissionFailed(t *testing.T) {
 	require.Error(t, c.SaveUploadedFile(f, "test/permission_test", mode))
 }
 
+func TestSaveUploadedFileChmodFailed(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skip("chmod test not applicable on Windows")
+	}
+	
+	buf := new(bytes.Buffer)
+	mw := multipart.NewWriter(buf)
+	w, err := mw.CreateFormFile("file", "chmod_test")
+	require.NoError(t, err)
+	_, err = w.Write([]byte("chmod_test"))
+	require.NoError(t, err)
+	mw.Close()
+	c, _ := CreateTestContext(httptest.NewRecorder())
+	c.Request, _ = http.NewRequest(http.MethodPost, "/", buf)
+	c.Request.Header.Set("Content-Type", mw.FormDataContentType())
+	f, err := c.FormFile("file")
+	require.NoError(t, err)
+	assert.Equal(t, "chmod_test", f.Filename)
+	
+	// Create a temporary directory with restricted permissions
+	tmpDir := t.TempDir()
+	restrictedDir := filepath.Join(tmpDir, "restricted")
+	require.NoError(t, os.MkdirAll(restrictedDir, 0o755))
+	// Make the directory read-only to trigger chmod failure
+	require.NoError(t, os.Chmod(restrictedDir, 0o444))
+	t.Cleanup(func() {
+		// Restore permissions for cleanup
+		os.Chmod(restrictedDir, 0o755)
+	})
+	
+	// Try to save file with different permissions - this should fail on chmod
+	var mode fs.FileMode = 0o755
+	err = c.SaveUploadedFile(f, filepath.Join(restrictedDir, "subdir", "chmod_test"), mode)
+	// This might fail on MkdirAll or Chmod depending on the system
+	assert.Error(t, err)
+}
+
 func TestContextReset(t *testing.T) {
 	router := New()
 	c := router.allocateContext(0)
@@ -896,6 +1227,20 @@ func TestContextQueryAndPostForm(t *testing.T) {
 	assert.Empty(t, dicts)
 }
 
+func TestContextInitFormCacheError(t *testing.T) {
+	c, _ := CreateTestContext(httptest.NewRecorder())
+	// Create a request with invalid multipart form data
+	body := strings.NewReader("invalid multipart data")
+	c.Request, _ = http.NewRequest(http.MethodPost, "/", body)
+	c.Request.Header.Set("Content-Type", "multipart/form-data; boundary=invalid")
+	c.engine.MaxMultipartMemory = 8 << 20
+
+	// This should trigger the error handling in initFormCache
+	values, ok := c.GetPostFormArray("foo")
+	assert.False(t, ok)
+	assert.Empty(t, values)
+}
+
 func TestContextPostFormMultipart(t *testing.T) {
 	c, _ := CreateTestContext(httptest.NewRecorder())
 	c.Request = createMultipartRequest()
@@ -2402,6 +2747,31 @@ func TestContextBadAutoShouldBind(t *testing.T) {
 	assert.False(t, c.IsAborted())
 }
 
+func TestContextShouldBindBodyWithReadError(t *testing.T) {
+	w := httptest.NewRecorder()
+	c, _ := CreateTestContext(w)
+	
+	// Create a request with a body that will cause read error
+	c.Request, _ = http.NewRequest(http.MethodPost, "/", &errorReader{})
+	
+	type testStruct struct {
+		Foo string `json:"foo"`
+	}
+	obj := testStruct{}
+	
+	// This should trigger the error handling in ShouldBindBodyWith
+	err := c.ShouldBindBodyWith(&obj, binding.JSON)
+	assert.Error(t, err)
+	assert.Contains(t, err.Error(), "read error")
+}
+
+// errorReader is a helper struct that always returns an error when Read is called
+type errorReader struct{}
+
+func (e *errorReader) Read(p []byte) (n int, err error) {
+	return 0, errors.New("read error")
+}
+
 func TestContextShouldBindBodyWith(t *testing.T) {
 	type typeA struct {
 		Foo string `json:"foo" xml:"foo" binding:"required"`
@@ -2872,6 +3242,17 @@ func TestContextGetRawData(t *testing.T) {
 	assert.Equal(t, "Fetch binary post data", string(data))
 }
 
+func TestContextGetRawDataNilBody(t *testing.T) {
+	c, _ := CreateTestContext(httptest.NewRecorder())
+	c.Request, _ = http.NewRequest(http.MethodPost, "/", nil)
+	c.Request.Body = nil
+
+	data, err := c.GetRawData()
+	assert.Error(t, err)
+	assert.Nil(t, data)
+	assert.Contains(t, err.Error(), "cannot read nil body")
+}
+
 func TestContextRenderDataFromReader(t *testing.T) {
 	w := httptest.NewRecorder()
 	c, _ := CreateTestContext(w)
@@ -3460,6 +3841,24 @@ func TestContextSetCookieData(t *testing.T) {
 		setCookie := c.Writer.Header().Get("Set-Cookie")
 		assert.Contains(t, setCookie, "SameSite=None")
 	})
+
+	// Test that SameSiteDefaultMode uses context's sameSite setting
+	t.Run("SameSite=Default uses context setting", func(t *testing.T) {
+		c, _ := CreateTestContext(httptest.NewRecorder())
+		c.SetSameSite(http.SameSiteStrictMode)
+		cookie := &http.Cookie{
+			Name:     "user",
+			Value:    "gin",
+			Path:     "/",
+			Domain:   "localhost",
+			Secure:   true,
+			HttpOnly: true,
+			SameSite: http.SameSiteDefaultMode,
+		}
+		c.SetCookieData(cookie)
+		setCookie := c.Writer.Header().Get("Set-Cookie")
+		assert.Contains(t, setCookie, "SameSite=Strict")
+	})
 }
 
 func TestGetMapFromFormData(t *testing.T) {

debug_test.go

@@ -124,6 +124,59 @@ func TestDebugPrintWARNINGDefaultWithUnsupportedVersion(t *testing.T) {
 	assert.Equal(t, "[GIN-debug] [WARNING] Now Gin requires Go 1.24+.\n\n[GIN-debug] [WARNING] Creating an Engine instance with the Logger and Recovery middleware already attached.\n\n", re)
 }
 
+func TestDebugPrintWARNINGDefaultLowGoVersion(t *testing.T) {
+	// Test the Go version warning branch by testing getMinVer with different inputs
+	// and then testing the logic directly
+	
+	// First test getMinVer with a version that would trigger the warning
+	v, err := getMinVer("go1.22.1")
+	require.NoError(t, err)
+	assert.Equal(t, uint64(22), v)
+	
+	// Test that version 22 is less than ginSupportMinGoVer (23)
+	assert.True(t, v < ginSupportMinGoVer)
+	
+	// Test the warning message directly by capturing debugPrint output
+	re := captureOutput(t, func() {
+		SetMode(DebugMode)
+		// Simulate the condition that would trigger the warning
+		if v < ginSupportMinGoVer {
+			debugPrint(`[WARNING] Now Gin requires Go 1.23+.
+
+`)
+		}
+		debugPrint(`[WARNING] Creating an Engine instance with the Logger and Recovery middleware already attached.
+
+`)
+		SetMode(TestMode)
+	})
+	
+	assert.Equal(t, "[GIN-debug] [WARNING] Now Gin requires Go 1.23+.\n\n[GIN-debug] [WARNING] Creating an Engine instance with the Logger and Recovery middleware already attached.\n\n", re)
+}
+
+func TestDebugPrintWithCustomFunc(t *testing.T) {
+	// Test debugPrint with custom DebugPrintFunc
+	originalFunc := DebugPrintFunc
+	defer func() {
+		DebugPrintFunc = originalFunc
+	}()
+	
+	var capturedFormat string
+	var capturedValues []any
+	DebugPrintFunc = func(format string, values ...any) {
+		capturedFormat = format
+		capturedValues = values
+	}
+	
+	SetMode(DebugMode)
+	debugPrint("test %s %d", "message", 42)
+	SetMode(TestMode)
+	
+	// debugPrint automatically adds \n if not present
+	assert.Equal(t, "test %s %d", capturedFormat)
+	assert.Equal(t, []any{"message", 42}, capturedValues)
+}
+
 func TestDebugPrintWARNINGNew(t *testing.T) {
 	re := captureOutput(t, func() {
 		SetMode(DebugMode)

recovery.go

@@ -5,7 +5,9 @@
 package gin
 
 import (
+	"bufio"
 	"bytes"
+	"cmp"
 	"errors"
 	"fmt"
 	"io"
@@ -21,9 +23,10 @@ import (
 	"github.com/gin-gonic/gin/internal/bytesconv"
 )
 
-const dunno = "???"
-
-var dunnoBytes = []byte(dunno)
+const (
+	dunno     = "???"
+	stackSkip = 3
+)
 
 // RecoveryFunc defines the function passable to CustomRecovery.
 type RecoveryFunc func(c *Context, err any)
@@ -72,7 +75,6 @@ func CustomRecoveryWithWriter(out io.Writer, handle RecoveryFunc) HandlerFunc {
 					brokenPipe = true
 				}
 				if logger != nil {
-					const stackSkip = 3
 					if brokenPipe {
 						logger.Printf("%s\n%s%s", err, secureRequestDump(c.Request), reset)
 					} else if IsDebugging() {
@@ -120,8 +122,11 @@ func stack(skip int) []byte {
 	buf := new(bytes.Buffer) // the returned data
 	// As we loop, we open files and read them. These variables record the currently
 	// loaded file.
-	var lines [][]byte
-	var lastFile string
+	var (
+		nLine    string
+		lastFile string
+		err      error
+	)
 	for i := skip; ; i++ { // Skip the expected number of frames
 		pc, file, line, ok := runtime.Caller(i)
 		if !ok {
@@ -130,25 +135,44 @@ func stack(skip int) []byte {
 		// Print this much at least.  If we can't find the source, it won't show.
 		fmt.Fprintf(buf, "%s:%d (0x%x)\n", file, line, pc)
 		if file != lastFile {
-			data, err := os.ReadFile(file)
+			nLine, err = readNthLine(file, line-1)
 			if err != nil {
 				continue
 			}
-			lines = bytes.Split(data, []byte{'\n'})
 			lastFile = file
 		}
-		fmt.Fprintf(buf, "\t%s: %s\n", function(pc), source(lines, line))
+		fmt.Fprintf(buf, "\t%s: %s\n", function(pc), cmp.Or(nLine, dunno))
 	}
 	return buf.Bytes()
 }
 
-// source returns a space-trimmed slice of the n'th line.
-func source(lines [][]byte, n int) []byte {
-	n-- // in stack trace, lines are 1-indexed but our array is 0-indexed
-	if n < 0 || n >= len(lines) {
-		return dunnoBytes
+// readNthLine reads the nth line from the file.
+// It returns the trimmed content of the line if found,
+// or an empty string if the line doesn't exist.
+// If there's an error opening the file, it returns the error.
+func readNthLine(file string, n int) (string, error) {
+	if n < 0 {
+		return "", nil
 	}
-	return bytes.TrimSpace(lines[n])
+
+	f, err := os.Open(file)
+	if err != nil {
+		return "", err
+	}
+	defer f.Close()
+
+	scanner := bufio.NewScanner(f)
+	for i := 0; i < n; i++ {
+		if !scanner.Scan() {
+			return "", nil
+		}
+	}
+
+	if scanner.Scan() {
+		return strings.TrimSpace(scanner.Text()), nil
+	}
+
+	return "", nil
 }
 
 // function returns, if possible, the name of the function containing the PC.

recovery_test.go

@@ -88,21 +88,6 @@ func TestPanicWithAbort(t *testing.T) {
 	assert.Equal(t, http.StatusBadRequest, w.Code)
 }
 
-func TestSource(t *testing.T) {
-	bs := source(nil, 0)
-	assert.Equal(t, dunnoBytes, bs)
-
-	in := [][]byte{
-		[]byte("Hello world."),
-		[]byte("Hi, gin.."),
-	}
-	bs = source(in, 10)
-	assert.Equal(t, dunnoBytes, bs)
-
-	bs = source(in, 1)
-	assert.Equal(t, []byte("Hello world."), bs)
-}
-
 func TestFunction(t *testing.T) {
 	bs := function(1)
 	assert.Equal(t, dunno, bs)
@@ -331,3 +316,53 @@ func TestSecureRequestDump(t *testing.T) {
 		})
 	}
 }
+
+// TestReadNthLine tests the readNthLine function with various scenarios.
+func TestReadNthLine(t *testing.T) {
+	// Create a temporary test file
+	testContent := "line 0 \n line 1  \nline 2 \nline 3  \nline 4"
+	tempFile, err := os.CreateTemp("", "testfile*.txt")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.Remove(tempFile.Name())
+
+	// Write test content to the temporary file
+	if _, err := tempFile.WriteString(testContent); err != nil {
+		t.Fatal(err)
+	}
+	if err := tempFile.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	// Test cases
+	tests := []struct {
+		name     string
+		lineNum  int
+		fileName string
+		want     string
+		wantErr  bool
+	}{
+		{name: "Read first line", lineNum: 0, fileName: tempFile.Name(), want: "line 0", wantErr: false},
+		{name: "Read middle line", lineNum: 2, fileName: tempFile.Name(), want: "line 2", wantErr: false},
+		{name: "Read last line", lineNum: 4, fileName: tempFile.Name(), want: "line 4", wantErr: false},
+		{name: "Line number exceeds file length", lineNum: 10, fileName: tempFile.Name(), want: "", wantErr: false},
+		{name: "Negative line number", lineNum: -1, fileName: tempFile.Name(), want: "", wantErr: false},
+		{name: "Non-existent file", lineNum: 1, fileName: "/non/existent/file.txt", want: "", wantErr: true},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := readNthLine(tt.fileName, tt.lineNum)
+			assert.Equal(t, tt.wantErr, err != nil)
+			assert.Equal(t, tt.want, got)
+		})
+	}
+}
+
+func BenchmarkStack(b *testing.B) {
+	b.ReportAllocs()
+	for b.Loop() {
+		_ = stack(stackSkip)
+	}
+}

tree.go

@@ -5,7 +5,6 @@
 package gin
 
 import (
-	"math"
 	"net/url"
 	"strings"
 	"unicode"
@@ -78,14 +77,6 @@ func (n *node) addChild(child *node) {
 	}
 }
 
-// safeUint16 converts int to uint16 safely, capping at math.MaxUint16
-func safeUint16(n int) uint16 {
-	if n > math.MaxUint16 {
-		return math.MaxUint16
-	}
-	return uint16(n)
-}
-
 func countParams(path string) uint16 {
 	colons := strings.Count(path, ":")
 	stars := strings.Count(path, "*")

utils.go

@@ -6,6 +6,7 @@ package gin
 
 import (
 	"encoding/xml"
+	"math"
 	"net/http"
 	"os"
 	"path"
@@ -162,3 +163,19 @@ func isASCII(s string) bool {
 	}
 	return true
 }
+
+// safeInt8 converts int to int8 safely, capping at math.MaxInt8
+func safeInt8(n int) int8 {
+	if n > math.MaxInt8 {
+		return math.MaxInt8
+	}
+	return int8(n)
+}
+
+// safeUint16 converts int to uint16 safely, capping at math.MaxUint16
+func safeUint16(n int) uint16 {
+	if n > math.MaxUint16 {
+		return math.MaxUint16
+	}
+	return uint16(n)
+}

utils_test.go

@@ -8,6 +8,7 @@ import (
 	"bytes"
 	"encoding/xml"
 	"fmt"
+	"math"
 	"net/http"
 	"testing"
 
@@ -148,3 +149,13 @@ func TestIsASCII(t *testing.T) {
 	assert.True(t, isASCII("test"))
 	assert.False(t, isASCII("🧡💛💚💙💜"))
 }
+
+func TestSafeInt8(t *testing.T) {
+	assert.Equal(t, int8(100), safeInt8(100))
+	assert.Equal(t, int8(math.MaxInt8), safeInt8(int(math.MaxInt8)+123))
+}
+
+func TestSafeUint16(t *testing.T) {
+	assert.Equal(t, uint16(100), safeUint16(100))
+	assert.Equal(t, uint16(math.MaxUint16), safeUint16(int(math.MaxUint16)+123))
+}