WIP: Experimental Unit Tests without Display (#900)

* Experimental test for unit tests without display

* Ignore unit tests running on an invalid QT Platform (i.e. offscreen - running as a test on GitHub)

* Fix whitespace on Caption effect

* Check for env variable for QT_QPA_PLATFORM == offscreen, and ignore Caption unit tests (for GitHub checks)

Author: jonoomph

.github/workflows/ci.yml

@@ -202,6 +202,9 @@ jobs:
 
       - name: Test libopenshot
         run: |
+          # Allow unit tests which require a display screen
+          export DISPLAY=:0.0
+          export QT_QPA_PLATFORM=offscreen
           cmake --build build --target coverage -- VERBOSE=1
 
       - name: Install libopenshot

src/effects/Caption.cpp

@@ -204,10 +204,10 @@ std::shared_ptr<openshot::Frame> Caption::GetFrame(std::shared_ptr<openshot::Fra
 				// Wrap languages which do not use spaces
 				bool use_spaces = true;
 				if (line.length() > 20 && words.length() == 1) {
-                    words = line.split("");
-                    use_spaces = false;
+					words = line.split("");
+					use_spaces = false;
 				}
-                int words_remaining = words.length();
+				int words_remaining = words.length();
 				while (words_remaining > 0) {
 					bool words_displayed = false;
 					for(int word_index = words.length(); word_index > 0; word_index--) {
@@ -222,11 +222,11 @@ std::shared_ptr<openshot::Frame> Caption::GetFrame(std::shared_ptr<openshot::Fra
 
 							// Create path and add text to it (for correct border and fill)
 							QPainterPath path1;
-                            QString fitting_line;
+							QString fitting_line;
 							if (use_spaces) {
-                                fitting_line = words.mid(0, word_index).join(" ");
+								fitting_line = words.mid(0, word_index).join(" ");
 							} else {
-                                fitting_line = words.mid(0, word_index).join("");
+								fitting_line = words.mid(0, word_index).join("");
 							}
 							path1.addText(p, font, fitting_line);
 							text_paths.push_back(path1);

tests/Caption.cpp

@@ -23,6 +23,15 @@
 
 TEST_CASE( "caption effect", "[libopenshot][caption]" )
 {
+    // Check for QT Platform Environment variable - and ignore these tests if it's set to offscreen
+    if (std::getenv("QT_QPA_PLATFORM") != nullptr) {
+        std::string qt_platform_env = std::getenv("QT_QPA_PLATFORM");
+        if (qt_platform_env == "offscreen") {
+            std::cout << "Ignoring Caption unit tests due to invalid QT Platform: offscreen" << std::endl;
+            return;
+        }
+    }
+
     int argc;
     char* argv[2];
     QGuiApplication::setAttribute(Qt::AA_EnableHighDpiScaling);