widevine-partner/ce_cdm
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Source release 19.5.0

Browse Source
This commit is contained in:
Cong Lin
2025-04-02 10:27:18 -07:00
parent 4407acee62
commit f7ec4fdeff
295 changed files with 32196 additions and 21748 deletions
Download Patch File Download Diff File Expand all files Collapse all files

415
third_party/googletest/docs/advanced.md vendored
View File

@@ -1,9 +1,9 @@
# Advanced googletest Topics
# Advanced GoogleTest Topics
## Introduction
Now that you have read the [googletest Primer](primer.md) and learned how to
write tests using googletest, it's time to learn some new tricks. This document
Now that you have read the [GoogleTest Primer](primer.md) and learned how to
write tests using GoogleTest, it's time to learn some new tricks. This document
will show you more assertions as well as how to construct complex failure
messages, propagate fatal failures, reuse and speed up your test fixtures, and
use various flags with your tests.
@@ -25,7 +25,7 @@ Reference.
### Predicate Assertions for Better Error Messages
Even though googletest has a rich set of assertions, they can never be complete,
Even though GoogleTest has a rich set of assertions, they can never be complete,
as it's impossible (nor a good idea) to anticipate all scenarios a user might
run into. Therefore, sometimes a user has to use `EXPECT_TRUE()` to check a
complex expression, for lack of a better macro. This has the problem of not
@@ -35,7 +35,7 @@ failure message by themselves, streaming it into `EXPECT_TRUE()`. However, this
is awkward especially when the expression has side-effects or is expensive to
evaluate.
googletest gives you three different options to solve this problem:
GoogleTest gives you three different options to solve this problem:
#### Using an Existing Boolean Function
@@ -286,7 +286,7 @@ For example:
```c++
TEST(SkipTest, DoesSkip) {
GTEST_SKIP() << "Skipping single test";
EXPECT_EQ(0, 1); // Won't fail; it won't be executed
FAIL(); // Won't fail; it won't be executed
}
class SkipFixture : public ::testing::Test {
@@ -298,15 +298,15 @@ class SkipFixture : public ::testing::Test {
// Tests for SkipFixture won't be executed.
TEST_F(SkipFixture, SkipsOneTest) {
EXPECT_EQ(5, 7); // Won't fail
FAIL(); // Won't fail; it won't be executed
}
```
As with assertion macros, you can stream a custom message into `GTEST_SKIP()`.
## Teaching googletest How to Print Your Values
## Teaching GoogleTest How to Print Your Values
When a test assertion such as `EXPECT_EQ` fails, googletest prints the argument
When a test assertion such as `EXPECT_EQ` fails, GoogleTest prints the argument
values to help you debug. It does this using a user-extensible value printer.
This printer knows how to print built-in C++ types, native arrays, STL
@@ -315,73 +315,141 @@ prints the raw bytes in the value and hopes that you the user can figure it out.
As mentioned earlier, the printer is *extensible*. That means you can teach it
to do a better job at printing your particular type than to dump the bytes. To
do that, define `<<` for your type:
```c++
#include <ostream>
do that, define an `AbslStringify()` overload as a `friend` function template
for your type:
```cpp
namespace foo {
class Bar { // We want googletest to be able to print instances of this.
...
// Create a free inline friend function.
friend std::ostream& operator<<(std::ostream& os, const Bar& bar) {
return os << bar.DebugString(); // whatever needed to print bar to os
class Point { // We want GoogleTest to be able to print instances of this.
...
// Provide a friend overload.
template <typename Sink>
friend void AbslStringify(Sink& sink, const Point& point) {
absl::Format(&sink, "(%d, %d)", point.x, point.y);
}
int x;
int y;
};
// If you can't declare the function in the class it's important that the
// << operator is defined in the SAME namespace that defines Bar. C++'s look-up
// rules rely on that.
std::ostream& operator<<(std::ostream& os, const Bar& bar) {
return os << bar.DebugString(); // whatever needed to print bar to os
// AbslStringify overload is defined in the SAME namespace that defines Point.
// C++'s look-up rules rely on that.
enum class EnumWithStringify { kMany = 0, kChoices = 1 };
template <typename Sink>
void AbslStringify(Sink& sink, EnumWithStringify e) {
absl::Format(&sink, "%s", e == EnumWithStringify::kMany ? "Many" : "Choices");
}
} // namespace foo
```
Sometimes, this might not be an option: your team may consider it bad style to
have a `<<` operator for `Bar`, or `Bar` may already have a `<<` operator that
doesn't do what you want (and you cannot change it). If so, you can instead
define a `PrintTo()` function like this:
{: .callout .note}
Note: `AbslStringify()` utilizes a generic "sink" buffer to construct its
string. For more information about supported operations on `AbslStringify()`'s
sink, see go/abslstringify.
`AbslStringify()` can also use `absl::StrFormat`'s catch-all `%v` type specifier
within its own format strings to perform type deduction. `Point` above could be
formatted as `"(%v, %v)"` for example, and deduce the `int` values as `%d`.
Sometimes, `AbslStringify()` might not be an option: your team may wish to print
types with extra debugging information for testing purposes only. If so, you can
instead define a `PrintTo()` function like this:
```c++
#include <ostream>
namespace foo {
class Bar {
class Point {
...
friend void PrintTo(const Bar& bar, std::ostream* os) {
*os << bar.DebugString(); // whatever needed to print bar to os
friend void PrintTo(const Point& point, std::ostream* os) {
*os << "(" << point.x << "," << point.y << ")";
}
int x;
int y;
};
// If you can't declare the function in the class it's important that PrintTo()
// is defined in the SAME namespace that defines Bar. C++'s look-up rules rely
// on that.
void PrintTo(const Bar& bar, std::ostream* os) {
*os << bar.DebugString(); // whatever needed to print bar to os
// is defined in the SAME namespace that defines Point. C++'s look-up rules
// rely on that.
void PrintTo(const Point& point, std::ostream* os) {
*os << "(" << point.x << "," << point.y << ")";
}
} // namespace foo
```
If you have defined both `<<` and `PrintTo()`, the latter will be used when
googletest is concerned. This allows you to customize how the value appears in
googletest's output without affecting code that relies on the behavior of its
`<<` operator.
If you have defined both `AbslStringify()` and `PrintTo()`, the latter will be
used by GoogleTest. This allows you to customize how the value appears in
GoogleTest's output without affecting code that relies on the behavior of
`AbslStringify()`.
If you want to print a value `x` using googletest's value printer yourself, just
If you have an existing `<<` operator and would like to define an
`AbslStringify()`, the latter will be used for GoogleTest printing.
If you want to print a value `x` using GoogleTest's value printer yourself, just
call `::testing::PrintToString(x)`, which returns an `std::string`:
```c++
vector<pair<Bar, int> > bar_ints = GetBarIntVector();
vector<pair<Point, int> > point_ints = GetPointIntVector();
EXPECT_TRUE(IsCorrectBarIntVector(bar_ints))
<< "bar_ints = " << testing::PrintToString(bar_ints);
EXPECT_TRUE(IsCorrectPointIntVector(point_ints))
<< "point_ints = " << testing::PrintToString(point_ints);
```
For more details regarding `AbslStringify()` and its integration with other
libraries, see go/abslstringify.
## Regular Expression Syntax
When built with Bazel and using Abseil, GoogleTest uses the
[RE2](https://github.com/google/re2/wiki/Syntax) syntax. Otherwise, for POSIX
systems (Linux, Cygwin, Mac), GoogleTest uses the
[POSIX extended regular expression](https://pubs.opengroup.org/onlinepubs/009695399/basedefs/xbd_chap09.html#tag_09_04)
syntax. To learn about POSIX syntax, you may want to read this
[Wikipedia entry](https://en.wikipedia.org/wiki/Regular_expression#POSIX_extended).
On Windows, GoogleTest uses its own simple regular expression implementation. It
lacks many features. For example, we don't support union (`"x|y"`), grouping
(`"(xy)"`), brackets (`"[xy]"`), and repetition count (`"x{5,7}"`), among
others. Below is what we do support (`A` denotes a literal character, period
(`.`), or a single `\\ ` escape sequence; `x` and `y` denote regular
expressions.):
Expression | Meaning
---------- | --------------------------------------------------------------
`c` | matches any literal character `c`
`\\d` | matches any decimal digit
`\\D` | matches any character that's not a decimal digit
`\\f` | matches `\f`
`\\n` | matches `\n`
`\\r` | matches `\r`
`\\s` | matches any ASCII whitespace, including `\n`
`\\S` | matches any character that's not a whitespace
`\\t` | matches `\t`
`\\v` | matches `\v`
`\\w` | matches any letter, `_`, or decimal digit
`\\W` | matches any character that `\\w` doesn't match
`\\c` | matches any literal character `c`, which must be a punctuation
`.` | matches any single character except `\n`
`A?` | matches 0 or 1 occurrences of `A`
`A*` | matches 0 or many occurrences of `A`
`A+` | matches 1 or many occurrences of `A`
`^` | matches the beginning of a string (not that of each line)
`$` | matches the end of a string (not that of each line)
`xy` | matches `x` followed by `y`
To help you determine which capability is available on your system, GoogleTest
defines macros to govern which regular expression it is using. The macros are:
`GTEST_USES_SIMPLE_RE=1` or `GTEST_USES_POSIX_RE=1`. If you want your death
tests to work in all cases, you can either `#if` on these macros or use the more
limited syntax only.
## Death Tests
In many applications, there are assertions that can cause application failure if
@@ -393,7 +461,7 @@ corruption, security holes, or worse. Hence it is vitally important to test that
such assertion statements work as expected.
Since these precondition checks cause the processes to die, we call such tests
_death tests_. More generally, any test that checks that a program terminates
*death tests*. More generally, any test that checks that a program terminates
(except by throwing an exception) in an expected fashion is also a death test.
Note that if a piece of code throws an exception, we don't consider it "death"
@@ -439,6 +507,12 @@ verifies that:
exit with exit code 0, and
* calling `KillProcess()` kills the process with signal `SIGKILL`.
{: .callout .warning}
Warning: If your death test contains mocks and is expecting a specific exit
code, then you must allow the mock objects to be leaked via `Mock::AllowLeak`.
This is because the mock leak detector will exit with its own error code if it
detects a leak.
The test function body may contain other assertions and statements as well, if
necessary.
@@ -451,7 +525,7 @@ Note that a death test only cares about three things:
3. does the stderr output match `matcher`?
In particular, if `statement` generates an `ASSERT_*` or `EXPECT_*` failure, it
will **not** cause the death test to fail, as googletest assertions don't abort
will **not** cause the death test to fail, as GoogleTest assertions don't abort
the process.
### Death Test Naming
@@ -480,49 +554,6 @@ TEST_F(FooDeathTest, DoesThat) {
}
```
### Regular Expression Syntax
On POSIX systems (e.g. Linux, Cygwin, and Mac), googletest uses the
[POSIX extended regular expression](http://www.opengroup.org/onlinepubs/009695399/basedefs/xbd_chap09.html#tag_09_04)
syntax. To learn about this syntax, you may want to read this
[Wikipedia entry](http://en.wikipedia.org/wiki/Regular_expression#POSIX_Extended_Regular_Expressions).
On Windows, googletest uses its own simple regular expression implementation. It
lacks many features. For example, we don't support union (`"x|y"`), grouping
(`"(xy)"`), brackets (`"[xy]"`), and repetition count (`"x{5,7}"`), among
others. Below is what we do support (`A` denotes a literal character, period
(`.`), or a single `\\ ` escape sequence; `x` and `y` denote regular
expressions.):
Expression | Meaning
---------- | --------------------------------------------------------------
`c` | matches any literal character `c`
`\\d` | matches any decimal digit
`\\D` | matches any character that's not a decimal digit
`\\f` | matches `\f`
`\\n` | matches `\n`
`\\r` | matches `\r`
`\\s` | matches any ASCII whitespace, including `\n`
`\\S` | matches any character that's not a whitespace
`\\t` | matches `\t`
`\\v` | matches `\v`
`\\w` | matches any letter, `_`, or decimal digit
`\\W` | matches any character that `\\w` doesn't match
`\\c` | matches any literal character `c`, which must be a punctuation
`.` | matches any single character except `\n`
`A?` | matches 0 or 1 occurrences of `A`
`A*` | matches 0 or many occurrences of `A`
`A+` | matches 1 or many occurrences of `A`
`^` | matches the beginning of a string (not that of each line)
`$` | matches the end of a string (not that of each line)
`xy` | matches `x` followed by `y`
To help you determine which capability is available on your system, googletest
defines macros to govern which regular expression it is using. The macros are:
`GTEST_USES_SIMPLE_RE=1` or `GTEST_USES_POSIX_RE=1`. If you want your death
tests to work in all cases, you can either `#if` on these macros or use the more
limited syntax only.
### How It Works
See [Death Assertions](reference/assertions.md#death) in the Assertions
@@ -537,7 +568,7 @@ arrange that kind of environment. For example, statically-initialized modules
may start threads before main is ever reached. Once threads have been created,
it may be difficult or impossible to clean them up.
googletest has three features intended to raise awareness of threading issues.
GoogleTest has three features intended to raise awareness of threading issues.
1. A warning is emitted if multiple threads are running when a death test is
encountered.
@@ -560,7 +591,7 @@ The automated testing framework does not set the style flag. You can choose a
particular style of death tests by setting the flag programmatically:
```c++
GTEST_FLAG_SET(death_test_style, "threadsafe")
GTEST_FLAG_SET(death_test_style, "threadsafe");
```
You can do this in `main()` to set the style for all death tests in the binary,
@@ -590,7 +621,7 @@ TEST(MyDeathTest, TestTwo) {
The `statement` argument of `ASSERT_EXIT()` can be any valid C++ statement. If
it leaves the current function via a `return` statement or by throwing an
exception, the death test is considered to have failed. Some googletest macros
exception, the death test is considered to have failed. Some GoogleTest macros
may return from the current function (e.g. `ASSERT_TRUE()`), so be sure to avoid
them in `statement`.
@@ -702,7 +733,7 @@ Some tips on using `SCOPED_TRACE`:
### Propagating Fatal Failures
A common pitfall when using `ASSERT_*` and `FAIL*` is not understanding that
when they fail they only abort the _current function_, not the entire test. For
when they fail they only abort the *current function*, not the entire test. For
example, the following test will segfault:
```c++
@@ -724,7 +755,7 @@ TEST(FooTest, Bar) {
}
```
To alleviate this, googletest provides three different solutions. You could use
To alleviate this, GoogleTest provides three different solutions. You could use
either exceptions, the `(ASSERT|EXPECT)_NO_FATAL_FAILURE` assertions or the
`HasFatalFailure()` function. They are described in the following two
subsections.
@@ -758,7 +789,7 @@ in it, the test will continue after the subroutine returns. This may not be what
you want.
Often people want fatal failures to propagate like exceptions. For that
googletest offers the following macros:
GoogleTest offers the following macros:
Fatal assertion | Nonfatal assertion | Verifies
------------------------------------- | ------------------------------------- | --------
@@ -839,7 +870,7 @@ will output XML like this:
```xml
...
<testcase name="MinAndMaxWidgets" status="run" time="0.006" classname="WidgetUsageTest" MaximumWidgets="12" MinimumWidgets="9" />
<testcase name="MinAndMaxWidgets" file="test.cpp" line="1" status="run" time="0.006" classname="WidgetUsageTest" MaximumWidgets="12" MinimumWidgets="9" />
...
```
@@ -850,7 +881,7 @@ will output XML like this:
> needs to be prefixed with `::testing::Test::` if used outside of the
> `TEST` body and the test fixture class.
> * *`key`* must be a valid XML attribute name, and cannot conflict with the
> ones already used by googletest (`name`, `status`, `time`, `classname`,
> ones already used by GoogleTest (`name`, `status`, `time`, `classname`,
> `type_param`, and `value_param`).
> * Calling `RecordProperty()` outside of the lifespan of a test is allowed.
> If it's called outside of a test but between a test suite's
@@ -861,25 +892,25 @@ will output XML like this:
## Sharing Resources Between Tests in the Same Test Suite
googletest creates a new test fixture object for each test in order to make
GoogleTest creates a new test fixture object for each test in order to make
tests independent and easier to debug. However, sometimes tests use resources
that are expensive to set up, making the one-copy-per-test model prohibitively
expensive.
If the tests don't change the resource, there's no harm in their sharing a
single resource copy. So, in addition to per-test set-up/tear-down, googletest
single resource copy. So, in addition to per-test set-up/tear-down, GoogleTest
also supports per-test-suite set-up/tear-down. To use it:
1. In your test fixture class (say `FooTest` ), declare as `static` some member
variables to hold the shared resources.
2. Outside your test fixture class (typically just below it), define those
member variables, optionally giving them initial values.
3. In the same test fixture class, define a `static void SetUpTestSuite()`
function (remember not to spell it as **`SetupTestSuite`** with a small
`u`!) to set up the shared resources and a `static void TearDownTestSuite()`
function to tear them down.
3. In the same test fixture class, define a public member function `static void
SetUpTestSuite()` (remember not to spell it as **`SetupTestSuite`** with a
small `u`!) to set up the shared resources and a `static void
TearDownTestSuite()` function to tear them down.
That's it! googletest automatically calls `SetUpTestSuite()` before running the
That's it! GoogleTest automatically calls `SetUpTestSuite()` before running the
*first test* in the `FooTest` test suite (i.e. before creating the first
`FooTest` object), and calls `TearDownTestSuite()` after running the *last test*
in it (i.e. after deleting the last `FooTest` object). In between, the tests can
@@ -894,7 +925,8 @@ Note that `SetUpTestSuite()` may be called multiple times for a test fixture
class that has derived classes, so you should not expect code in the function
body to be run only once. Also, derived classes still have access to shared
resources defined as static members, so careful consideration is needed when
managing shared resources to avoid memory leaks.
managing shared resources to avoid memory leaks if shared resources are not
properly cleaned up in `TearDownTestSuite()`.
Here's an example of per-test-suite set-up and tear-down:
@@ -905,10 +937,15 @@ class FooTest : public testing::Test {
// Called before the first test in this test suite.
// Can be omitted if not needed.
static void SetUpTestSuite() {
// Avoid reallocating static objects if called in subclasses of FooTest.
if (shared_resource_ == nullptr) {
shared_resource_ = new ...;
}
shared_resource_ = new ...;
// If `shared_resource_` is **not deleted** in `TearDownTestSuite()`,
// reallocation should be prevented because `SetUpTestSuite()` may be called
// in subclasses of FooTest and lead to memory leak.
//
// if (shared_resource_ == nullptr) {
// shared_resource_ = new ...;
// }
}
// Per-test-suite tear-down.
@@ -966,24 +1003,34 @@ class Environment : public ::testing::Environment {
};
```
Then, you register an instance of your environment class with googletest by
Then, you register an instance of your environment class with GoogleTest by
calling the `::testing::AddGlobalTestEnvironment()` function:
```c++
Environment* AddGlobalTestEnvironment(Environment* env);
```
Now, when `RUN_ALL_TESTS()` is called, it first calls the `SetUp()` method of
each environment object, then runs the tests if none of the environments
reported fatal failures and `GTEST_SKIP()` was not called. `RUN_ALL_TESTS()`
always calls `TearDown()` with each environment object, regardless of whether or
not the tests were run.
Now, when `RUN_ALL_TESTS()` is invoked, it first calls the `SetUp()` method. The
tests are then executed, provided that none of the environments have reported
fatal failures and `GTEST_SKIP()` has not been invoked. Finally, `TearDown()` is
called.
Note that `SetUp()` and `TearDown()` are only invoked if there is at least one
test to be performed. Importantly, `TearDown()` is executed even if the test is
not run due to a fatal failure or `GTEST_SKIP()`.
Calling `SetUp()` and `TearDown()` for each iteration depends on the flag
`gtest_recreate_environments_when_repeating`. `SetUp()` and `TearDown()` are
called for each environment object when the object is recreated for each
iteration. However, if test environments are not recreated for each iteration,
`SetUp()` is called only on the first iteration, and `TearDown()` is called only
on the last iteration.
It's OK to register multiple environment objects. In this suite, their `SetUp()`
will be called in the order they are registered, and their `TearDown()` will be
called in the reverse order.
Note that googletest takes ownership of the registered environment objects.
Note that GoogleTest takes ownership of the registered environment objects.
Therefore **do not delete them** by yourself.
You should call `AddGlobalTestEnvironment()` before `RUN_ALL_TESTS()` is called,
@@ -1035,7 +1082,7 @@ they must be declared **public** rather than **protected** in order to use
```c++
class FooTest :
public testing::TestWithParam<const char*> {
public testing::TestWithParam<absl::string_view> {
// You can implement all the usual fixture class members here.
// To access the test parameter, call GetParam() from class
// TestWithParam<T>.
@@ -1046,7 +1093,7 @@ class BaseTest : public testing::Test {
...
};
class BarTest : public BaseTest,
public testing::WithParamInterface<const char*> {
public testing::WithParamInterface<absl::string_view> {
...
};
```
@@ -1093,6 +1140,11 @@ instantiation of the test suite. The next argument is the name of the test
pattern, and the last is the
[parameter generator](reference/testing.md#param-generators).
The parameter generator expression is not evaluated until GoogleTest is
initialized (via `InitGoogleTest()`). Any prior initialization done in the
`main` function will be accessible from the parameter generator, for example,
the results of flag parsing.
You can instantiate a test pattern more than once, so to distinguish different
instances of the pattern, the instantiation name is added as a prefix to the
actual test suite name. Remember to pick unique prefixes for different
@@ -1112,8 +1164,8 @@ with parameter values `"cat"` and `"dog"` using the
[`ValuesIn`](reference/testing.md#param-generators) parameter generator:
```c++
const char* pets[] = {"cat", "dog"};
INSTANTIATE_TEST_SUITE_P(Pets, FooTest, testing::ValuesIn(pets));
constexpr absl::string_view kPets[] = {"cat", "dog"};
INSTANTIATE_TEST_SUITE_P(Pets, FooTest, testing::ValuesIn(kPets));
```
The tests from the instantiation above will have these names:
@@ -1140,8 +1192,8 @@ GTEST_ALLOW_UNINSTANTIATED_PARAMETERIZED_TEST(FooTest);
You can see [sample7_unittest.cc] and [sample8_unittest.cc] for more examples.
[sample7_unittest.cc]: https://github.com/google/googletest/blob/master/googletest/samples/sample7_unittest.cc "Parameterized Test example"
[sample8_unittest.cc]: https://github.com/google/googletest/blob/master/googletest/samples/sample8_unittest.cc "Parameterized Test example with multiple parameters"
[sample7_unittest.cc]: https://github.com/google/googletest/blob/main/googletest/samples/sample7_unittest.cc "Parameterized Test example"
[sample8_unittest.cc]: https://github.com/google/googletest/blob/main/googletest/samples/sample8_unittest.cc "Parameterized Test example with multiple parameters"
### Creating Value-Parameterized Abstract Tests
@@ -1292,7 +1344,7 @@ TYPED_TEST(FooTest, HasPropertyA) { ... }
You can see [sample6_unittest.cc] for a complete example.
[sample6_unittest.cc]: https://github.com/google/googletest/blob/master/googletest/samples/sample6_unittest.cc "Typed Test example"
[sample6_unittest.cc]: https://github.com/google/googletest/blob/main/googletest/samples/sample6_unittest.cc "Typed Test example"
## Type-Parameterized Tests
@@ -1313,6 +1365,7 @@ First, define a fixture class template, as we did with typed tests:
```c++
template <typename T>
class FooTest : public testing::Test {
void DoSomethingInteresting();
...
};
```
@@ -1330,6 +1383,9 @@ this as many times as you want:
TYPED_TEST_P(FooTest, DoesBlah) {
// Inside a test, refer to TypeParam to get the type parameter.
TypeParam n = 0;
// You will need to use `this` explicitly to refer to fixture members.
this->DoSomethingInteresting()
...
}
@@ -1484,12 +1540,12 @@ To test them, we use the following special techniques:
## "Catching" Failures
If you are building a testing utility on top of googletest, you'll want to test
your utility. What framework would you use to test it? googletest, of course.
If you are building a testing utility on top of GoogleTest, you'll want to test
your utility. What framework would you use to test it? GoogleTest, of course.
The challenge is to verify that your testing utility reports failures correctly.
In frameworks that report a failure by throwing an exception, you could catch
the exception and assert on it. But googletest doesn't use exceptions, so how do
the exception and assert on it. But GoogleTest doesn't use exceptions, so how do
we test that a piece of code generates an expected failure?
`"gtest/gtest-spi.h"` contains some constructs to do this.
@@ -1632,9 +1688,9 @@ particular, you cannot find the test suite name in `SetUpTestSuite()`,
`TearDownTestSuite()` (where you know the test suite name implicitly), or
functions called from them.
## Extending googletest by Handling Test Events
## Extending GoogleTest by Handling Test Events
googletest provides an **event listener API** to let you receive notifications
GoogleTest provides an **event listener API** to let you receive notifications
about the progress of a test program and test failures. The events you can
listen to include the start and end of the test program, a test suite, or a test
method, among others. You may use this API to augment or replace the standard
@@ -1695,7 +1751,7 @@ Here's an example:
### Using Event Listeners
To use the event listener you have defined, add an instance of it to the
googletest event listener list (represented by class
GoogleTest event listener list (represented by class
[`TestEventListeners`](reference/testing.md#TestEventListeners) - note the "s"
at the end of the name) in your `main()` function, before calling
`RUN_ALL_TESTS()`:
@@ -1706,7 +1762,7 @@ int main(int argc, char** argv) {
// Gets hold of the event listener list.
testing::TestEventListeners& listeners =
testing::UnitTest::GetInstance()->listeners();
// Adds a listener to the end. googletest takes the ownership.
// Adds a listener to the end. GoogleTest takes the ownership.
listeners.Append(new MinimalistPrinter);
return RUN_ALL_TESTS();
}
@@ -1727,7 +1783,7 @@ You can do so by adding one line:
Now, sit back and enjoy a completely different output from your tests. For more
details, see [sample9_unittest.cc].
[sample9_unittest.cc]: https://github.com/google/googletest/blob/master/googletest/samples/sample9_unittest.cc "Event listener example"
[sample9_unittest.cc]: https://github.com/google/googletest/blob/main/googletest/samples/sample9_unittest.cc "Event listener example"
You may append more than one listener to the list. When an `On*Start()` or
`OnTestPartResult()` event is fired, the listeners will receive it in the order
@@ -1754,17 +1810,17 @@ by the former.
See [sample10_unittest.cc] for an example of a failure-raising listener.
[sample10_unittest.cc]: https://github.com/google/googletest/blob/master/googletest/samples/sample10_unittest.cc "Failure-raising listener example"
[sample10_unittest.cc]: https://github.com/google/googletest/blob/main/googletest/samples/sample10_unittest.cc "Failure-raising listener example"
## Running Test Programs: Advanced Options
googletest test programs are ordinary executables. Once built, you can run them
GoogleTest test programs are ordinary executables. Once built, you can run them
directly and affect their behavior via the following environment variables
and/or command line flags. For the flags to work, your programs must call
`::testing::InitGoogleTest()` before calling `RUN_ALL_TESTS()`.
To see a list of supported flags and their usage, please run your test program
with the `--help` flag. You can also use `-h`, `-?`, or `/?` for short.
with the `--help` flag.
If an option is specified both by an environment variable and by a flag, the
latter takes precedence.
@@ -1791,10 +1847,10 @@ corresponding environment variable for this flag.
#### Running a Subset of the Tests
By default, a googletest program runs all tests the user has defined. Sometimes,
By default, a GoogleTest program runs all tests the user has defined. Sometimes,
you want to run only a subset of the tests (e.g. for debugging or quickly
verifying a change). If you set the `GTEST_FILTER` environment variable or the
`--gtest_filter` flag to a filter string, googletest will only run the tests
`--gtest_filter` flag to a filter string, GoogleTest will only run the tests
whose full names (in the form of `TestSuiteName.TestName`) match the filter.
The format of a filter is a '`:`'-separated list of wildcard patterns (called
@@ -1825,7 +1881,7 @@ For example:
#### Stop test execution upon first failure
By default, a googletest program runs all tests the user has defined. In some
By default, a GoogleTest program runs all tests the user has defined. In some
cases (e.g. iterative test development & execution) it may be desirable stop
test execution upon first failure (trading improved latency for completeness).
If `GTEST_FAIL_FAST` environment variable or `--gtest_fail_fast` flag is set,
@@ -1842,7 +1898,7 @@ If you need to disable all tests in a test suite, you can either add `DISABLED_`
to the front of the name of each test, or alternatively add it to the front of
the test suite name.
For example, the following tests won't be run by googletest, even though they
For example, the following tests won't be run by GoogleTest, even though they
will still be compiled:
```c++
@@ -1857,7 +1913,7 @@ TEST_F(DISABLED_BarTest, DoesXyz) { ... }
{: .callout .note}
NOTE: This feature should only be used for temporary pain-relief. You still have
to fix the disabled tests at a later date. As a reminder, googletest will print
to fix the disabled tests at a later date. As a reminder, GoogleTest will print
a banner warning you if a test program contains any disabled tests.
{: .callout .tip}
@@ -1873,6 +1929,20 @@ the `--gtest_also_run_disabled_tests` flag or set the
You can combine this with the `--gtest_filter` flag to further select which
disabled tests to run.
### Enforcing Having At Least One Test Case
A not uncommon programmer mistake is to write a test program that has no test
case linked in. This can happen, for example, when you put test case definitions
in a library and the library is not marked as "always link".
To catch such mistakes, run the test program with the
`--gtest_fail_if_no_test_linked` flag or set the `GTEST_FAIL_IF_NO_TEST_LINKED`
environment variable to a value other than `0`. Now the program will fail if no
test case is linked in.
Note that *any* test case linked in makes the program valid for the purpose of
this check. In particular, even a disabled test case suffices.
### Repeating the Tests
Once in a while you'll run into a test whose result is hit-or-miss. Perhaps it
@@ -1902,8 +1972,12 @@ Repeat the tests whose name matches the filter 1000 times.
If your test program contains
[global set-up/tear-down](#global-set-up-and-tear-down) code, it will be
repeated in each iteration as well, as the flakiness may be in it. You can also
specify the repeat count by setting the `GTEST_REPEAT` environment variable.
repeated in each iteration as well, as the flakiness may be in it. To avoid
repeating global set-up/tear-down, specify
`--gtest_recreate_environments_when_repeating=false`{.nowrap}.
You can also specify the repeat count by setting the `GTEST_REPEAT` environment
variable.
### Shuffling the Tests
@@ -1911,16 +1985,16 @@ You can specify the `--gtest_shuffle` flag (or set the `GTEST_SHUFFLE`
environment variable to `1`) to run the tests in a program in a random order.
This helps to reveal bad dependencies between tests.
By default, googletest uses a random seed calculated from the current time.
By default, GoogleTest uses a random seed calculated from the current time.
Therefore you'll get a different order every time. The console output includes
the random seed value, such that you can reproduce an order-related test failure
later. To specify the random seed explicitly, use the `--gtest_random_seed=SEED`
flag (or set the `GTEST_RANDOM_SEED` environment variable), where `SEED` is an
integer in the range [0, 99999]. The seed value 0 is special: it tells
googletest to do the default behavior of calculating the seed from the current
GoogleTest to do the default behavior of calculating the seed from the current
time.
If you combine this with `--gtest_repeat=N`, googletest will pick a different
If you combine this with `--gtest_repeat=N`, GoogleTest will pick a different
random seed and re-shuffle the tests in each iteration.
### Distributing Test Functions to Multiple Machines
@@ -1979,7 +2053,7 @@ shards, but here's one possible scenario:
#### Colored Terminal Output
googletest can use colors in its terminal output to make it easier to spot the
GoogleTest can use colors in its terminal output to make it easier to spot the
important information:
<pre>...
@@ -2004,25 +2078,25 @@ important information:
You can set the `GTEST_COLOR` environment variable or the `--gtest_color`
command line flag to `yes`, `no`, or `auto` (the default) to enable colors,
disable colors, or let googletest decide. When the value is `auto`, googletest
disable colors, or let GoogleTest decide. When the value is `auto`, GoogleTest
will use colors if and only if the output goes to a terminal and (on non-Windows
platforms) the `TERM` environment variable is set to `xterm` or `xterm-color`.
#### Suppressing test passes
By default, googletest prints 1 line of output for each test, indicating if it
By default, GoogleTest prints 1 line of output for each test, indicating if it
passed or failed. To show only test failures, run the test program with
`--gtest_brief=1`, or set the GTEST_BRIEF environment variable to `1`.
#### Suppressing the Elapsed Time
By default, googletest prints the time it takes to run each test. To disable
By default, GoogleTest prints the time it takes to run each test. To disable
that, run the test program with the `--gtest_print_time=0` command line flag, or
set the GTEST_PRINT_TIME environment variable to `0`.
#### Suppressing UTF-8 Text Output
In case of assertion failures, googletest prints expected and actual values of
In case of assertion failures, GoogleTest prints expected and actual values of
type `string` both as hex-encoded strings as well as in readable UTF-8 text if
they contain valid non-ASCII UTF-8 characters. If you want to suppress the UTF-8
text because, for example, you don't have an UTF-8 compatible output medium, run
@@ -2031,7 +2105,7 @@ environment variable to `0`.
#### Generating an XML Report
googletest can emit a detailed XML report to a file in addition to its normal
GoogleTest can emit a detailed XML report to a file in addition to its normal
textual output. The report contains the duration of each test, and thus can help
you identify slow tests.
@@ -2042,15 +2116,15 @@ in which case the output can be found in the `test_detail.xml` file in the
current directory.
If you specify a directory (for example, `"xml:output/directory/"` on Linux or
`"xml:output\directory\"` on Windows), googletest will create the XML file in
`"xml:output\directory\"` on Windows), GoogleTest will create the XML file in
that directory, named after the test executable (e.g. `foo_test.xml` for test
program `foo_test` or `foo_test.exe`). If the file already exists (perhaps left
over from a previous run), googletest will pick a different name (e.g.
over from a previous run), GoogleTest will pick a different name (e.g.
`foo_test_1.xml`) to avoid overwriting it.
The report is based on the `junitreport` Ant task. Since that format was
originally intended for Java, a little interpretation is required to make it
apply to googletest tests, as shown here:
apply to GoogleTest tests, as shown here:
```xml
<testsuites name="AllTests" ...>
@@ -2065,8 +2139,8 @@ apply to googletest tests, as shown here:
```
* The root `<testsuites>` element corresponds to the entire test program.
* `<testsuite>` elements correspond to googletest test suites.
* `<testcase>` elements correspond to googletest test functions.
* `<testsuite>` elements correspond to GoogleTest test suites.
* `<testcase>` elements correspond to GoogleTest test functions.
For instance, the following program
@@ -2082,15 +2156,15 @@ could generate this report:
<?xml version="1.0" encoding="UTF-8"?>
<testsuites tests="3" failures="1" errors="0" time="0.035" timestamp="2011-10-31T18:52:42" name="AllTests">
<testsuite name="MathTest" tests="2" failures="1" errors="0" time="0.015">
<testcase name="Addition" status="run" time="0.007" classname="">
<testcase name="Addition" file="test.cpp" line="1" status="run" time="0.007" classname="">
<failure message="Value of: add(1, 1)&#x0A; Actual: 3&#x0A;Expected: 2" type="">...</failure>
<failure message="Value of: add(1, -1)&#x0A; Actual: 1&#x0A;Expected: 0" type="">...</failure>
</testcase>
<testcase name="Subtraction" status="run" time="0.005" classname="">
<testcase name="Subtraction" file="test.cpp" line="2" status="run" time="0.005" classname="">
</testcase>
</testsuite>
<testsuite name="LogicTest" tests="1" failures="0" errors="0" time="0.005">
<testcase name="NonContradiction" status="run" time="0.005" classname="">
<testcase name="NonContradiction" file="test.cpp" line="3" status="run" time="0.005" classname="">
</testcase>
</testsuite>
</testsuites>
@@ -2099,7 +2173,7 @@ could generate this report:
Things to note:
* The `tests` attribute of a `<testsuites>` or `<testsuite>` element tells how
many test functions the googletest program or test suite contains, while the
many test functions the GoogleTest program or test suite contains, while the
`failures` attribute tells how many of them failed.
* The `time` attribute expresses the duration of the test, test suite, or
@@ -2108,12 +2182,15 @@ Things to note:
* The `timestamp` attribute records the local date and time of the test
execution.
* Each `<failure>` element corresponds to a single failed googletest
* The `file` and `line` attributes record the source file location, where the
test was defined.
* Each `<failure>` element corresponds to a single failed GoogleTest
assertion.
#### Generating a JSON Report
googletest can also emit a JSON report as an alternative format to XML. To
GoogleTest can also emit a JSON report as an alternative format to XML. To
generate the JSON report, set the `GTEST_OUTPUT` environment variable or the
`--gtest_output` flag to the string `"json:path_to_output_file"`, which will
create the file at the given location. You can also just use the string
@@ -2124,7 +2201,7 @@ The report format conforms to the following JSON Schema:
```json
{
"$schema": "http://json-schema.org/schema#",
"$schema": "https://json-schema.org/schema#",
"type": "object",
"definitions": {
"TestCase": {
@@ -2147,6 +2224,8 @@ The report format conforms to the following JSON Schema:
"type": "object",
"properties": {
"name": { "type": "string" },
"file": { "type": "string" },
"line": { "type": "integer" },
"status": {
"type": "string",
"enum": ["RUN", "NOTRUN"]
@@ -2224,6 +2303,8 @@ message TestCase {
message TestInfo {
string name = 1;
string file = 6;
int32 line = 7;
enum Status {
RUN = 0;
NOTRUN = 1;
@@ -2267,6 +2348,8 @@ could generate this report:
"testsuite": [
{
"name": "Addition",
"file": "test.cpp",
"line": 1,
"status": "RUN",
"time": "0.007s",
"classname": "",
@@ -2283,6 +2366,8 @@ could generate this report:
},
{
"name": "Subtraction",
"file": "test.cpp",
"line": 2,
"status": "RUN",
"time": "0.005s",
"classname": ""
@@ -2298,6 +2383,8 @@ could generate this report:
"testsuite": [
{
"name": "NonContradiction",
"file": "test.cpp",
"line": 3,
"status": "RUN",
"time": "0.005s",
"classname": ""
@@ -2315,7 +2402,7 @@ IMPORTANT: The exact format of the JSON document is subject to change.
#### Detecting Test Premature Exit
Google Test implements the _premature-exit-file_ protocol for test runners to
Google Test implements the *premature-exit-file* protocol for test runners to
catch any kind of unexpected exits of test programs. Upon start, Google Test
creates the file which will be automatically deleted after all work has been
finished. Then, the test runner can check if this file exists. In case the file
@@ -2328,7 +2415,7 @@ variable has been set.
When running test programs under a debugger, it's very convenient if the
debugger can catch an assertion failure and automatically drop into interactive
mode. googletest's *break-on-failure* mode supports this behavior.
mode. GoogleTest's *break-on-failure* mode supports this behavior.
To enable it, set the `GTEST_BREAK_ON_FAILURE` environment variable to a value
other than `0`. Alternatively, you can use the `--gtest_break_on_failure`
@@ -2336,9 +2423,9 @@ command line flag.
#### Disabling Catching Test-Thrown Exceptions
googletest can be used either with or without exceptions enabled. If a test
GoogleTest can be used either with or without exceptions enabled. If a test
throws a C++ exception or (on Windows) a structured exception (SEH), by default
googletest catches it, reports it as a test failure, and continues with the next
GoogleTest catches it, reports it as a test failure, and continues with the next
test method. This maximizes the coverage of a test run. Also, on Windows an
uncaught exception will cause a pop-up window, so catching the exceptions allows
you to run the tests automatically.
@@ -2376,4 +2463,4 @@ void __tsan_on_report() {
```
After compiling your project with one of the sanitizers enabled, if a particular
test triggers a sanitizer error, googletest will report that it failed.
test triggers a sanitizer error, GoogleTest will report that it failed.