src/runtime/panic_test.go

// Copyright 2020 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package runtime_test

import (
	"strings"
	"testing"
)

// Test that panics print out the underlying value
// when the underlying kind is directly printable.
// Issue: https://golang.org/issues/37531
func TestPanicWithDirectlyPrintableCustomTypes(t *testing.T) {
	tests := []struct {
		name            string
		wantPanicPrefix string
	}{
		{"panicCustomBool", `panic: main.MyBool(true)`},
		{"panicCustomComplex128", `panic: main.MyComplex128(32.1+10i)`},
		{"panicCustomComplex64", `panic: main.MyComplex64(0.11+3i)`},
		{"panicCustomFloat32", `panic: main.MyFloat32(-93.7)`},
		{"panicCustomFloat64", `panic: main.MyFloat64(-93.7)`},
		{"panicCustomInt", `panic: main.MyInt(93)`},
		{"panicCustomInt8", `panic: main.MyInt8(93)`},
		{"panicCustomInt16", `panic: main.MyInt16(93)`},
		{"panicCustomInt32", `panic: main.MyInt32(93)`},
		{"panicCustomInt64", `panic: main.MyInt64(93)`},
		{"panicCustomString", `panic: main.MyString("Panic` + "\n\t" + `line two")`},
		{"panicCustomUint", `panic: main.MyUint(93)`},
		{"panicCustomUint8", `panic: main.MyUint8(93)`},
		{"panicCustomUint16", `panic: main.MyUint16(93)`},
		{"panicCustomUint32", `panic: main.MyUint32(93)`},
		{"panicCustomUint64", `panic: main.MyUint64(93)`},
		{"panicCustomUintptr", `panic: main.MyUintptr(93)`},
		{"panicDeferFatal", "panic: runtime.errorString(\"invalid memory address or nil pointer dereference\")\n\tfatal error: sync: unlock of unlocked mutex"},
		{"panicDoublieDeferFatal", "panic: runtime.errorString(\"invalid memory address or nil pointer dereference\") [recovered, repanicked]\n\tfatal error: sync: unlock of unlocked mutex"},
	}

	for _, tt := range tests {
		t := t
		t.Run(tt.name, func(t *testing.T) {
			output := runTestProg(t, "testprog", tt.name)
			if !strings.HasPrefix(output, tt.wantPanicPrefix) {
				t.Fatalf("%q\nis not present in\n%s", tt.wantPanicPrefix, output)
			}
		})
	}
}