Call stack perf change for CallerInfo

assert/assertions.go

@@ -24,6 +24,8 @@ import (
 	"github.com/stretchr/testify/assert/yaml"
 )
 
+const stackFrameBufferSize = 10
+
 //go:generate sh -c "cd ../_codegen && go build && cd - && ../_codegen/_codegen -output-package=assert -template=assertion_format.go.tmpl"
 
 // TestingT is an interface wrapper around *testing.T
@@ -212,19 +214,26 @@ the problem actually occurred in calling code.*/
 func CallerInfo() []string {
 
 	var pc uintptr
-	var ok bool
 	var file string
 	var line int
 	var name string
 
 	callers := []string{}
-	for i := 0; ; i++ {
-		pc, file, line, ok = runtime.Caller(i)
-		if !ok {
-			// The breaks below failed to terminate the loop, and we ran off the
-			// end of the call stack.
-			break
-		}
+	pcs := make([]uintptr, stackFrameBufferSize)
+	offset := 1
+	n := runtime.Callers(offset, pcs)
+	maybeMore := n == stackFrameBufferSize
+
+	if n == 0 {
+		return []string{}
+	}
+	frames := runtime.CallersFrames(pcs[:n])
+
+	for {
+		frame, more := frames.Next()
+		pc = frame.PC
+		file = frame.File
+		line = frame.Line
 
 		// This is a huge edge case, but it will panic if this is the case, see #180
 		if file == "<autogenerated>" {
@@ -263,6 +272,23 @@ func CallerInfo() []string {
 			isTest(name, "Example") {
 			break
 		}
+
+		if !more {
+			// We know we already have less than a buffer's worth of frames
+			if !maybeMore {
+				break
+			}
+			offset += stackFrameBufferSize
+			n = runtime.Callers(offset, pcs)
+			if n == 0 {
+				break
+			}
+
+			maybeMore = n == stackFrameBufferSize
+
+			frames = runtime.CallersFrames(pcs[:n])
+		}
+
 	}
 
 	return callers