CppEditor: Fix insert position of AddIncludeForUndefinedIdentifier

If there are no includes, add new include at the top of file but skip
possible comments at the beginning.

Task-number: QTCREATORBUG-8799
Change-Id: Ie2be644f6ad0a948cf3d8700efa00087753d9863
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>

src/plugins/cppeditor/cppplugin.h

@@ -125,6 +125,11 @@ private slots:
     void test_quickfix_InsertDefFromDecl_headerSource_namespace1();
     void test_quickfix_InsertDefFromDecl_headerSource_namespace2();
     void test_quickfix_InsertDefFromDecl_freeFunction();
+
+    void test_quickfix_AddIncludeForUndefinedIdentifier_normal();
+    void test_quickfix_AddIncludeForUndefinedIdentifier_noinclude();
+    void test_quickfix_AddIncludeForUndefinedIdentifier_noincludeComment01();
+    void test_quickfix_AddIncludeForUndefinedIdentifier_noincludeComment02();
 #endif // WITH_TESTS
 
 private:

src/plugins/cppeditor/cppquickfix_test.cpp

@@ -881,3 +881,165 @@ void CppPlugin::test_quickfix_InsertDefFromDecl_freeFunction()
     TestCase data(original, expected);
     data.run(&factory);
 }
+
+/// Check normal add include if there is already a include
+void CppPlugin::test_quickfix_AddIncludeForUndefinedIdentifier_normal()
+{
+    QList<TestDocumentPtr> testFiles;
+
+    QByteArray original;
+    QByteArray expected;
+
+    // Header File
+    original = "class Foo {};\n";
+    expected = original + "\n";
+    testFiles << TestDocument::create(original, expected, QLatin1String("file.h"));
+
+    // Source File
+    original =
+        "#include \"someheader.h\"\n"
+        "\n"
+        "void f()\n"
+        "{\n"
+        "    Fo@o foo;\n"
+        "}\n"
+        ;
+    expected =
+        "#include \"someheader.h\"\n"
+        "#include \"file.h\"\n"
+        "\n"
+        "void f()\n"
+        "{\n"
+        "    Foo foo;\n"
+        "}\n"
+        "\n"
+        ;
+    testFiles << TestDocument::create(original, expected, QLatin1String("file.cpp"));
+
+    AddIncludeForUndefinedIdentifier factory;
+    TestCase data(testFiles);
+    data.run(&factory);
+}
+
+/// Check add include if no include is present
+void CppPlugin::test_quickfix_AddIncludeForUndefinedIdentifier_noinclude()
+{
+    QList<TestDocumentPtr> testFiles;
+
+    QByteArray original;
+    QByteArray expected;
+
+    // Header File
+    original = "class Foo {};\n";
+    expected = original + "\n";
+    testFiles << TestDocument::create(original, expected, QLatin1String("file.h"));
+
+    // Source File
+    original =
+        "void f()\n"
+        "{\n"
+        "    Fo@o foo;\n"
+        "}\n"
+        ;
+    expected =
+        "#include \"file.h\"\n"
+        "\n"
+        "void f()\n"
+        "{\n"
+        "    Foo foo;\n"
+        "}\n"
+        "\n"
+        ;
+    testFiles << TestDocument::create(original, expected, QLatin1String("file.cpp"));
+
+    AddIncludeForUndefinedIdentifier factory;
+    TestCase data(testFiles);
+    data.run(&factory);
+}
+
+/// Check add include if no include is present with comment on top
+void CppPlugin::test_quickfix_AddIncludeForUndefinedIdentifier_noincludeComment01()
+{
+    QList<TestDocumentPtr> testFiles;
+
+    QByteArray original;
+    QByteArray expected;
+
+    // Header File
+    original = "class Foo {};\n";
+    expected = original + "\n";
+    testFiles << TestDocument::create(original, expected, QLatin1String("file.h"));
+
+    // Source File
+    original =
+        "\n"
+        "// comment\n"
+        "\n"
+        "void f()\n"
+        "{\n"
+        "    Fo@o foo;\n"
+        "}\n"
+        ;
+    expected =
+        "\n"
+        "// comment\n"
+        "\n"
+        "#include \"file.h\"\n"
+        "\n"
+        "void f()\n"
+        "{\n"
+        "    Foo foo;\n"
+        "}\n"
+        "\n"
+        ;
+    testFiles << TestDocument::create(original, expected, QLatin1String("file.cpp"));
+
+    AddIncludeForUndefinedIdentifier factory;
+    TestCase data(testFiles);
+    data.run(&factory);
+}
+/// Check add include if no include is present with comment on top
+void CppPlugin::test_quickfix_AddIncludeForUndefinedIdentifier_noincludeComment02()
+{
+    QList<TestDocumentPtr> testFiles;
+
+    QByteArray original;
+    QByteArray expected;
+
+    // Header File
+    original = "class Foo {};\n";
+    expected = original + "\n";
+    testFiles << TestDocument::create(original, expected, QLatin1String("file.h"));
+
+    // Source File
+    original =
+        "\n"
+        "/*\n"
+        " comment\n"
+        " */\n"
+        "\n"
+        "void f()\n"
+        "{\n"
+        "    Fo@o foo;\n"
+        "}\n"
+        ;
+    expected =
+        "\n"
+        "/*\n"
+        " comment\n"
+        " */\n"
+        "\n"
+        "#include \"file.h\"\n"
+        "\n"
+        "void f()\n"
+        "{\n"
+        "    Foo foo;\n"
+        "}\n"
+        "\n"
+        ;
+    testFiles << TestDocument::create(original, expected, QLatin1String("file.cpp"));
+
+    AddIncludeForUndefinedIdentifier factory;
+    TestCase data(testFiles);
+    data.run(&factory);
+}

src/plugins/cppeditor/cppquickfixes.cpp

@@ -1606,21 +1606,64 @@ public:
         CppRefactoringChanges refactoring(snapshot());
         CppRefactoringFilePtr file = refactoring.file(fileName());
 
-        // find location of last include in file
         QList<Document::Include> includes = file->cppDocument()->includes();
+        if (includes.isEmpty()) {
+            // No includes, find possible first/multi line comment
+            int insertPos = 0;
+            QTextBlock block = file->document()->firstBlock();
+            while (block.isValid()) {
+                const QString trimmedText = block.text().trimmed();
+
+                // Only skip the first comment!
+                if (trimmedText.startsWith(QLatin1String("/*"))) {
+                    do {
+                        const int pos = block.text().indexOf(QLatin1String("*/"));
+                        if (pos > -1) {
+                            insertPos = block.position() + pos + 2;
+                            break;
+                        }
+                        block = block.next();
+                    } while (block.isValid());
+                    break;
+                } else if (trimmedText.startsWith(QLatin1String("//"))) {
+                    block = block.next();
+                    while (block.isValid()) {
+                        if (!block.text().trimmed().startsWith(QLatin1String("//"))) {
+                            insertPos = block.position() - 1;
+                            break;
+                        }
+                        block = block.next();
+                    }
+                    break;
+                }
+
+                if (!trimmedText.isEmpty())
+                    break;
+                block = block.next();
+            }
+
+            ChangeSet changes;
+            if (insertPos != 0)
+                changes.insert(insertPos, QLatin1String("\n\n#include ") + m_include);
+            else
+                changes.insert(insertPos, QString::fromLatin1("#include %1\n\n").arg(m_include));
+            file->setChangeSet(changes);
+            file->apply();
+        } else {
+            // find location of last include in file
             unsigned lastIncludeLine = 0;
             foreach (const Document::Include &include, includes) {
                 if (include.line() > lastIncludeLine)
                     lastIncludeLine = include.line();
             }
 
-        // add include
+            const int insertPos = qMax(0, file->position(lastIncludeLine + 1, 1) - 1);
-        const int insertPos = file->position(lastIncludeLine + 1, 1) - 1;
             ChangeSet changes;
             changes.insert(insertPos, QLatin1String("\n#include ") + m_include);
             file->setChangeSet(changes);
             file->apply();
         }
+    }
 
 private:
     QString m_include;