Fix --exclude-directories option

.gitignore

@@ -1,6 +1,7 @@
 *.py[cod]
 
 # C extensions
+*.o
 *.so
 
 # Packages
@@ -22,9 +23,13 @@ lib64
 pip-log.txt
 
 # Unit test / coverage reports
+.pytest_cache/
 .coverage
+*.gcda
+*.gcno
 .tox
 nosetests.xml
+testcase
 
 # Translations
 *.mo

AUTHORS.txt

@@ -26,6 +26,7 @@ The following developers contributed to gcovr (ordered alphabetically):
     libPhipp,
     Lukas Atkinson,
     Luke Woydziak,
+    Marek Kurdej,
     Martin Mraz,
     Matsumoto Taichi,
     Matthew Stadelman,

doc/source/guide.rst

@@ -288,6 +288,47 @@ This is useful mostly when running gcov yourself,
 and then invoking gcovr with :option:`-g`/:option:`--use-gcov-files`.
 But these filters also apply when gcov is launched by gcovr.
 
+Speeding up coverage data search
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The :option:`--exclude-directories` filter is used
+while searching for raw coverage data
+(or for existing ``.gcov`` files when :option:`--use-gcov-files` is active).
+This filter is matched against directory paths, not file paths.
+If a directory matches,
+all its contents (files and subdirectories) will be excluded from the search.
+For example, consider this build directory::
+
+    build/
+    ├─ main.o
+    ├─ main.gcda
+    ├─ main.gcno
+    ├─ a/
+    │  ├─ awesome_code.o
+    │  ├─ awesome_code.gcda
+    │  └─ awesome_code.gcno
+    └─ b/
+       ├─ better_code.o
+       ├─ better_code.gcda
+       └─ better_code.gcno
+
+If we run ``gcovr --exclude-directories 'build/a$'``,
+this will exclude anything in the ``build/a`` directory
+but will use the coverage data for ``better_code.o`` and ``main.o``.
+
+This can speed up gcovr when you have a complicated build directory structure.
+Consider also using the :option:`search_paths`
+or :option:`--object-directory` arguments
+to specify where gcovr starts searching.
+If you are unsure which directories are being searched,
+run gcovr in :option:`--verbose` mode.
+
+For each found coverage data file gcovr will invoke the ``gcov`` tool.
+This is typically the slowest part,
+and other filters can only be applied *after* this step.
+In some cases, parallel execution with the :option:`-j` option
+might be helpful to speed up processing.
+
 Filters for symlinks
 ~~~~~~~~~~~~~~~~~~~~
 

gcovr/tests/exclude-directories-relative/Makefile

@@ -0,0 +1,28 @@
+CFLAGS= -fprofile-arcs -ftest-coverage -fPIC
+
+all:
+	mkdir -p build/a build/b
+	$(CXX) $(CFLAGS) -c a/file1.cpp -o build/a/file1.o
+	$(CXX) $(CFLAGS) -c b/main.cpp -o build/b/main.o
+	$(CXX) $(CFLAGS) build/b/main.o build/a/file1.o -o testcase
+
+run: txt xml html
+
+GCOVR_TEST_OPTIONS = --exclude-directories 'build/a'
+
+txt:
+	./testcase
+	$(GCOVR) $(GCOVR_TEST_OPTIONS) -d -o coverage.txt
+
+xml:
+	./testcase
+	$(GCOVR) $(GCOVR_TEST_OPTIONS) -d -x -o coverage.xml
+
+html:
+	./testcase
+	$(GCOVR) $(GCOVR_TEST_OPTIONS) -d --html-details -o coverage.html
+
+clean:
+	rm -f testcase
+	rm -f *.gc* *.o
+	rm -f coverage.txt coverage.xml coverage*.html

gcovr/tests/exclude-directories-relative/README

@@ -0,0 +1,4 @@
+This test case was inspired by ticket #3884:
+
+   https://software.sandia.gov/trac/fast/ticket/3884
+

gcovr/tests/exclude-directories-relative/a/file1.cpp

@@ -0,0 +1,5 @@
+
+int bar()
+{
+return 0;
+}

gcovr/tests/exclude-directories-relative/b/main.cpp

@@ -0,0 +1,18 @@
+#include <iostream>
+
+int bar();
+
+int foo(int param) {
+  if (param) {
+     return 1; //std::cout << "param not null." << std::endl;
+  } else {
+     return 0; //std::cout << "param is null." << std::endl;
+  }
+}
+
+
+int main(int argc, char* argv[]) {
+  foo(bar());
+
+  return 0;
+}