1 files changed, 163 insertions, 0 deletions
diff --git a/contrib/catch2/docs/logging.md b/contrib/catch2/docs/logging.md
new file mode 100644
index 0000000..7970938
--- /dev/null
+++ b/contrib/catch2/docs/logging.md
@@ -0,0 +1,163 @@
+<a id="top"></a>
+# Logging macros
+
+Additional messages can be logged during a test case. Note that the messages logged with `INFO` are scoped and thus will not be reported if failure occurs in scope preceding the message declaration. An example:
+
+```cpp
+TEST_CASE("Foo") {
+    INFO("Test case start");
+    for (int i = 0; i < 2; ++i) {
+        INFO("The number is " << i);
+        CHECK(i == 0);
+    }
+}
+
+TEST_CASE("Bar") {
+    INFO("Test case start");
+    for (int i = 0; i < 2; ++i) {
+        INFO("The number is " << i);
+        CHECK(i == i);
+    }
+    CHECK(false);
+}
+```
+When the `CHECK` fails in the "Foo" test case, then two messages will be printed.
+```
+Test case start
+The number is 1
+```
+When the last `CHECK` fails in the "Bar" test case, then only one message will be printed: `Test case start`.
+
+## Logging without local scope
+
+> [Introduced](https://github.com/catchorg/Catch2/issues/1522) in Catch2 2.7.0.
+
+`UNSCOPED_INFO` is similar to `INFO` with two key differences:
+
+- Lifetime of an unscoped message is not tied to its own scope.
+- An unscoped message can be reported by the first following assertion only, regardless of the result of that assertion.
+
+In other words, lifetime of `UNSCOPED_INFO` is limited by the following assertion (or by the end of test case/section, whichever comes first) whereas lifetime of `INFO` is limited by its own scope.
+
+These differences make this macro useful for reporting information from helper functions or inner scopes. An example:
+
+```cpp
+void print_some_info() {
+    UNSCOPED_INFO("Info from helper");
+}
+
+TEST_CASE("Baz") {
+    print_some_info();
+    for (int i = 0; i < 2; ++i) {
+        UNSCOPED_INFO("The number is " << i);
+    }
+    CHECK(false);
+}
+
+TEST_CASE("Qux") {
+    INFO("First info");
+    UNSCOPED_INFO("First unscoped info");
+    CHECK(false);
+
+    INFO("Second info");
+    UNSCOPED_INFO("Second unscoped info");
+    CHECK(false);
+}
+```
+
+"Baz" test case prints:
+```
+Info from helper
+The number is 0
+The number is 1
+```
+
+With "Qux" test case, two messages will be printed when the first `CHECK` fails:
+```
+First info
+First unscoped info
+```
+
+"First unscoped info" message will be cleared after the first `CHECK`, while "First info" message will persist until the end of the test case. Therefore, when the second `CHECK` fails, three messages will be printed:
+```
+First info
+Second info
+Second unscoped info
+```
+
+## Streaming macros
+
+All these macros allow heterogeneous sequences of values to be streaming using the insertion operator (```<<```) in the same way that std::ostream, std::cout, etc support it.
+
+E.g.:
+```c++
+INFO( "The number is " << i );
+```
+
+(Note that there is no initial ```<<``` - instead the insertion sequence is placed in parentheses.)
+These macros come in three forms:
+
+**INFO(** _message expression_ **)**
+
+The message is logged to a buffer, but only reported with next assertions that are logged. This allows you to log contextual information in case of failures which is not shown during a successful test run (for the console reporter, without -s). Messages are removed from the buffer at the end of their scope, so may be used, for example, in loops.
+
+_Note that in Catch2 2.x.x `INFO` can be used without a trailing semicolon as there is a trailing semicolon inside macro.
+This semicolon will be removed with next major version. It is highly advised to use a trailing semicolon after `INFO` macro._
+
+**UNSCOPED_INFO(** _message expression_ **)**
+
+> [Introduced](https://github.com/catchorg/Catch2/issues/1522) in Catch2 2.7.0.
+
+Similar to `INFO`, but messages are not limited to their own scope: They are removed from the buffer after each assertion, section or test case, whichever comes first.
+
+**WARN(** _message expression_ **)**
+
+The message is always reported but does not fail the test.
+
+**SUCCEED(** _message expression_ **)**
+
+The message is reported and the test case succeeds.
+
+**FAIL(** _message expression_ **)**
+
+The message is reported and the test case fails.
+
+**FAIL_CHECK(** _message expression_ **)**
+
+AS `FAIL`, but does not abort the test
+
+## Quickly capture value of variables or expressions
+
+**CAPTURE(** _expression1_, _expression2_, ... **)**
+
+Sometimes you just want to log a value of variable, or expression. For
+convenience, we provide the `CAPTURE` macro, that can take a variable,
+or an expression, and prints out that variable/expression and its value
+at the time of capture.
+
+e.g. `CAPTURE( theAnswer );` will log message "theAnswer := 42", while
+```cpp
+int a = 1, b = 2, c = 3;
+CAPTURE( a, b, c, a + b, c > b, a == 1);
+```
+will log a total of 6 messages:
+```
+a := 1
+b := 2
+c := 3
+a + b := 3
+c > b := true
+a == 1 := true
+```
+
+You can also capture expressions that use commas inside parentheses
+(e.g. function calls), brackets, or braces (e.g. initializers). To
+properly capture expression that contains template parameters list
+(in other words, it contains commas between angle brackets), you need
+to enclose the expression inside parentheses:
+`CAPTURE( (std::pair<int, int>{1, 2}) );`
+
+
+---
+
+[Home](Readme.md#top)