func()

in singleflight/singleflight.go [139:175]

• 27 lines of code
• 8 McCabe index (conditional complexity)

func (g *Group) doCall(c *call, key string, fn func() (interface{}, error)) {
	normalReturn := false
	recovered := false

	// use double-defer to distinguish panic from runtime.Goexit,
	// more details see https://golang.org/cl/134395
	defer func() {
		// the given function invoked runtime.Goexit
		if !normalReturn && !recovered {
			c.err = errGoexit
		}

		c.wg.Done()
		g.mu.Lock()
		defer g.mu.Unlock()
		if !c.forgotten {
			delete(g.m, key)
		}

		if e, ok := c.err.(*panicError); ok {
			// In order to prevent the waiting channels from being blocked forever,
			// needs to ensure that this panic cannot be recovered.
			if len(c.chans) > 0 {
				go panic(e)
				select {} // Keep this goroutine around so that it will appear in the crash dump.
			} else {
				panic(e)
			}
		} else if c.err == errGoexit {
			// Already in the process of goexit, no need to call again
		} else {
			// Normal return
			for _, ch := range c.chans {
				ch <- Result{c.val, c.err, c.dups > 0}
			}
		}
	}()