Improve <type-checks><unusedvar> error message (#4735)

Author: chrchr-github

lib/symboldatabase.cpp

@@ -2280,8 +2280,11 @@ std::string Variable::getTypeName() const
 {
     std::string ret;
     // TODO: For known types, generate the full type name
-    for (const Token *typeTok = mTypeStartToken; Token::Match(typeTok, "%name%|::") && typeTok->varId() == 0; typeTok = typeTok->next())
+    for (const Token *typeTok = mTypeStartToken; Token::Match(typeTok, "%name%|::") && typeTok->varId() == 0; typeTok = typeTok->next()) {
         ret += typeTok->str();
+        if (Token::simpleMatch(typeTok->next(), "<") && typeTok->next()->link()) // skip template arguments
+            typeTok = typeTok->next()->link();
+    }
     return ret;
 }
 

test/testbufferoverrun.cpp

@@ -207,6 +207,7 @@ class TestBufferOverrun : public TestFixture {
         TEST_CASE(array_index_negative4);
         TEST_CASE(array_index_negative5);    // #10526
         TEST_CASE(array_index_negative6);    // #11349
+        TEST_CASE(array_index_negative7);    // #5685
         TEST_CASE(array_index_for_decr);
         TEST_CASE(array_index_varnames);     // FP: struct member #1576, FN: #1586
         TEST_CASE(array_index_for_continue); // for,continue
@@ -2271,6 +2272,18 @@ class TestBufferOverrun : public TestFixture {
         ASSERT_EQUALS("", errout.str());
     }
 
+    // #5685
+    void array_index_negative7()
+    {
+        check("void f() {\n"
+              "    int i = -9;\n"
+              "    int a[5];\n"
+              "    for (; i < 5; i++)\n"
+              "        a[i] = 1;\n"
+              "}\n");
+        ASSERT_EQUALS("[test.cpp:5]: (error) Array 'a[5]' accessed at index -9, which is out of bounds.\n", errout.str());
+    }
+
     void array_index_for_decr() {
         check("void f()\n"
               "{\n"

test/testunusedvar.cpp

@@ -6270,6 +6270,11 @@ class TestUnusedVar : public TestFixture {
                               "    myManager.theDummyTable.addRow(UnsignedIndexValue{ myNewValue }, DummyRowData{ false });\n"
                               "}");
         ASSERT_EQUALS("", errout.str());
+
+        functionVariableUsage("void f() {\n"
+                              "    std::list<std::list<int>>::value_type a{ 1, 2, 3, 4 };\n"
+                              "}\n");
+        TODO_ASSERT_EQUALS("", "[test.cpp:2]: (information) --check-library: Provide <type-checks><unusedvar> configuration for std::list::value_type\n", errout.str());
     }
 
     void localvarRangeBasedFor() {