refactor(builder): Add failing test for ellipsis

Adds failing tests for the bug described in #1194

include/components/builder.hpp

@@ -59,6 +59,8 @@ class builder {
   string background_hex();
   string foreground_hex();
 
+  string get_label_text(const label_t& label);
+
   void tag_open(syntaxtag tag, const string& value);
   void tag_open(attribute attr);
   void tag_close(syntaxtag tag);

src/CMakeLists.txt

@@ -95,5 +95,7 @@ endif()
 
 # }}}
 
+# Export source file list so that it can be used for test compilation
+set(files ${files} PARENT_SCOPE)
 set(libs ${libs} PARENT_SCOPE)
 set(dirs ${dirs} PARENT_SCOPE)

src/components/builder.cpp

@@ -206,11 +206,7 @@ void builder::node(const label_t& label, bool add_space) {
     return;
   }
 
-  string text{label->get()};
-
-  if (label->m_maxlen > 0 && string_util::char_len(text) > label->m_maxlen) {
-    text = string_util::utf8_truncate(std::move(text), label->m_maxlen) + "...";
-  }
+  auto text = get_label_text(label);
 
   // if ((label->m_overline.empty() && m_tags[syntaxtag::o] > 0) || (m_tags[syntaxtag::o] > 0 && label->m_margin > 0))
   //   overline_close();
@@ -556,6 +552,16 @@ string builder::foreground_hex() {
   return m_foreground;
 }
 
+string builder::get_label_text(const label_t& label) {
+  string text{label->get()};
+
+  if (label->m_maxlen > 0 && string_util::char_len(text) > label->m_maxlen) {
+    text = string_util::utf8_truncate(std::move(text), label->m_maxlen) + "...";
+  }
+
+  return text;
+}
+
 /**
  * Insert directive to change value of given tag
  */

tests/CMakeLists.txt

@@ -44,7 +44,10 @@ function(unit_test file tests)
   # unit_test function become cleaner
   SET(sources "")
   FOREACH(f ${BIN_SOURCES})
-    LIST(APPEND sources "../src/${f}")
+    # Do not add main.cpp, because it will override the main function
+    if(NOT "${f}" STREQUAL "main.cpp")
+      LIST(APPEND sources "../src/${f}")
+    endif()
   ENDFOREACH(f)
 
   string(REPLACE "/" "_" testname ${file})
@@ -84,5 +87,9 @@ unit_test(components/command_line unit_tests
   utils/string.cpp)
 unit_test(components/bar unit_tests)
 
+unit_test(components/builder unit_tests
+  SOURCES
+  ${files})
+
 # Compile all unit tests with 'make all_unit_tests'
 add_custom_target("all_unit_tests" DEPENDS ${unit_tests})

tests/unit_tests/components/builder.cpp

@@ -0,0 +1,79 @@
+#include <tuple>
+
+#include "common/test.hpp"
+#include "components/builder.hpp"
+#include "components/types.hpp"
+#include "utils/factory.hpp"
+#include "drawtypes/label.hpp"
+
+using namespace polybar;
+using namespace std;
+
+/**
+ * \brief Testing-only subclass of builder to change access level
+ */
+class TestableBuilder : public builder {
+  using builder::builder;
+  public: using builder::get_label_text;
+};
+
+class Builder : public ::testing::Test {
+  protected:
+
+    /**
+     * Generic bar settings
+     *
+     * Builder only needs spacing and background
+     */
+    bar_settings m_bar{};
+    TestableBuilder m_builder{m_bar};
+};
+
+// GetLabelTextTest {{{
+
+/**
+ * \brief Class for parameterized tests on get_label_text
+ *
+ * The first element of the pair is the expected returned text, the second
+ * element is a triple containing the original label text, m_ellipsis and
+ * m_maxlen, in that order
+ */
+class GetLabelTextTest :
+  public Builder,
+  public ::testing::WithParamInterface<pair<string, tuple<string, bool, int>>> {};
+
+vector<pair<string, tuple<string, bool, int>>> get_label_text_list = {
+  {"...", make_tuple("abcd", true, 3)},
+  {"abc", make_tuple("abcdefgh", false, 3)},
+  {"a...", make_tuple("abcdefgh", true, 4)},
+  {"abcd...", make_tuple("abcdefgh", true, 7)},
+  {"abcdefgh", make_tuple("abcdefgh", true, 8)},
+};
+
+INSTANTIATE_TEST_CASE_P(Inst, GetLabelTextTest,
+    ::testing::ValuesIn(get_label_text_list),);
+
+TEST_P(GetLabelTextTest, correctness) {
+  label_t m_label = factory_util::shared<label>(get<0>(GetParam().second));
+  m_label->m_ellipsis = get<1>(GetParam().second);
+  m_label->m_maxlen = get<2>(GetParam().second);
+
+  auto text = m_builder.get_label_text(m_label);
+  EXPECT_EQ(GetParam().first, text);
+
+  EXPECT_LE(text.length(), m_label->m_maxlen) << "Returned text is longer than maxlen";
+}
+
+/**
+ * \brief Tests, if get_label_text throws an exception, when ellipsis is
+ *        turned on and m_maxlen is lower than 3 (length of the ellipsis)
+ */
+TEST_F(GetLabelTextTest, throwsException) {
+  label_t m_label = factory_util::shared<label>("abcdef");
+  m_label->m_ellipsis = true;
+  m_label->m_maxlen = 2;
+
+  EXPECT_ANY_THROW(m_builder.get_label_text(m_label));
+}
+
+// }}}