Initial euclide.org release

vendor/github.com/jarcoal/httpmock/internal/stack_tracer.go

@@ -0,0 +1,91 @@
+package internal
+
+import (
+	"bytes"
+	"fmt"
+	"net/http"
+	"runtime"
+	"strings"
+)
+
+type StackTracer struct {
+	CustomFn func(...interface{})
+	Err      error
+}
+
+// Error implements error interface.
+func (s StackTracer) Error() string {
+	if s.Err == nil {
+		return ""
+	}
+	return s.Err.Error()
+}
+
+// Unwrap implements the interface needed by errors.Unwrap.
+func (s StackTracer) Unwrap() error {
+	return s.Err
+}
+
+// CheckStackTracer checks for specific error returned by
+// NewNotFoundResponder function or Trace Responder method.
+func CheckStackTracer(req *http.Request, err error) error {
+	if nf, ok := err.(StackTracer); ok {
+		if nf.CustomFn != nil {
+			pc := make([]uintptr, 128)
+			npc := runtime.Callers(2, pc)
+			pc = pc[:npc]
+
+			var mesg bytes.Buffer
+			var netHTTPBegin, netHTTPEnd bool
+
+			// Start recording at first net/http call if any...
+			for {
+				frames := runtime.CallersFrames(pc)
+
+				var lastFn string
+				for {
+					frame, more := frames.Next()
+
+					if !netHTTPEnd {
+						if netHTTPBegin {
+							netHTTPEnd = !strings.HasPrefix(frame.Function, "net/http.")
+						} else {
+							netHTTPBegin = strings.HasPrefix(frame.Function, "net/http.")
+						}
+					}
+
+					if netHTTPEnd {
+						if lastFn != "" {
+							if mesg.Len() == 0 {
+								if nf.Err != nil {
+									mesg.WriteString(nf.Err.Error())
+								} else {
+									fmt.Fprintf(&mesg, "%s %s", req.Method, req.URL)
+								}
+								mesg.WriteString("\nCalled from ")
+							} else {
+								mesg.WriteString("\n  ")
+							}
+							fmt.Fprintf(&mesg, "%s()\n    at %s:%d", lastFn, frame.File, frame.Line)
+						}
+					}
+					lastFn = frame.Function
+
+					if !more {
+						break
+					}
+				}
+
+				// At least one net/http frame found
+				if mesg.Len() > 0 {
+					break
+				}
+				netHTTPEnd = true // retry without looking at net/http frames
+			}
+
+			nf.CustomFn(mesg.String())
+		}
+		err = nf.Err
+	}
+	return err
+}