feat: Improve code suggestions (#256)

test/LLMSuggestionTest.cpp

@@ -0,0 +1,157 @@
+/*
+ * Copyright (C) 2024-2025 Petr Mironychev
+ *
+ * This file is part of QodeAssist.
+ *
+ * QodeAssist is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * QodeAssist is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with QodeAssist. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include "LLMSuggestion.hpp"
+#include "TestUtils.hpp"
+
+#include <gtest/gtest.h>
+#include <QObject>
+#include <QString>
+
+using namespace QodeAssist;
+
+class LLMSuggestionTest : public QObject, public testing::Test
+{
+    Q_OBJECT
+};
+
+// Basic tests
+TEST_F(LLMSuggestionTest, testCalculateReplaceLengthEmptyRight)
+{
+    int result = LLMSuggestion::calculateReplaceLength("foo", "", "foo");
+    EXPECT_EQ(result, 0); // No rightText to replace
+}
+
+TEST_F(LLMSuggestionTest, testCalculateReplaceLengthNoOverlap)
+{
+    // No structural or token overlap
+    int result = LLMSuggestion::calculateReplaceLength("foo", "bar", "foobar");
+    EXPECT_EQ(result, 0); // Just insert, don't replace
+}
+
+// Structural overlap tests
+TEST_F(LLMSuggestionTest, testCalculateReplaceLengthStructuralBraces)
+{
+    // suggestion contains {}, rightText contains {}
+    int result = LLMSuggestion::calculateReplaceLength("= {\"red\"}", "{};", "colors{};");
+    EXPECT_EQ(result, 3); // Replace all rightText
+}
+
+TEST_F(LLMSuggestionTest, testCalculateReplaceLengthStructuralSemicolon)
+{
+    // suggestion contains ;, rightText contains ;
+    int result = LLMSuggestion::calculateReplaceLength("x;", ";", "int x;");
+    EXPECT_EQ(result, 1); // Replace the ;
+}
+
+TEST_F(LLMSuggestionTest, testCalculateReplaceLengthStructuralParens)
+{
+    // suggestion contains (), rightText contains )
+    int result = LLMSuggestion::calculateReplaceLength("arg1, arg2)", ")", "foo(arg1, arg2)");
+    EXPECT_EQ(result, 1); // Replace the )
+}
+
+TEST_F(LLMSuggestionTest, testCalculateReplaceLengthStructuralBrackets)
+{
+    // suggestion contains [], rightText contains ]
+    int result = LLMSuggestion::calculateReplaceLength("[0]", "];", "arr[0];");
+    EXPECT_EQ(result, 2); // Replace ];
+}
+
+// Token overlap tests
+TEST_F(LLMSuggestionTest, testCalculateReplaceLengthCommonToken)
+{
+    // suggestion contains "colors", entireLine contains "colors"
+    int result = LLMSuggestion::calculateReplaceLength("colors << \"red\"", "colors{};", "QStringList colors{};");
+    EXPECT_EQ(result, 9); // Replace all rightText due to common token
+}
+
+TEST_F(LLMSuggestionTest, testCalculateReplaceLengthMultipleCommonTokens)
+{
+    // Multiple tokens in common
+    int result = LLMSuggestion::calculateReplaceLength("engine.load()", "engine.rootContext()", "QmlEngine engine.rootContext()");
+    EXPECT_EQ(result, 20); // Replace all rightText
+}
+
+// Real-world scenarios
+TEST_F(LLMSuggestionTest, testCursorInBraces)
+{
+    // Cursor in braces: QStringList colors{<cursor>};
+    // LLM sends: "\"red\", \"green\"", rightText: "};"
+    // No common tokens ("red" and "green" are strings, not identifiers in entireLine)
+    // No structural overlap (suggestion doesn't contain } or ;)
+    int result = LLMSuggestion::calculateReplaceLength("\"red\", \"green\"", "};", "QStringList colors{};");
+    EXPECT_EQ(result, 0); // No overlap, just insert
+}
+
+TEST_F(LLMSuggestionTest, testCursorBeforeBraces)
+{
+    // Cursor before braces: QStringList colors<cursor>{};
+    // LLM sends: " = {\"red\"}", rightText: "{};"
+    int result = LLMSuggestion::calculateReplaceLength(" = {\"red\"}", "{};", "QStringList colors{};");
+    EXPECT_EQ(result, 3); // Structural overlap - replace all
+}
+
+TEST_F(LLMSuggestionTest, testCursorAfterType)
+{
+    // Cursor after type: QStringList <cursor>colors{};
+    // LLM sends: "colors << \"red\"", rightText: "colors{};"
+    int result = LLMSuggestion::calculateReplaceLength("colors << \"red\"", "colors{};", "QStringList colors{};");
+    EXPECT_EQ(result, 9); // Common token - replace all
+}
+
+TEST_F(LLMSuggestionTest, testCursorInMiddleNoConflict)
+{
+    // Cursor in middle: int <cursor>myVar = 5;
+    // LLM sends: "myVar", rightText: " = 5;", entireLine: "int myVar = 5;"
+    // "myVar" is a common token -> replace rightText
+    int result = LLMSuggestion::calculateReplaceLength("myVar", " = 5;", "int myVar = 5;");
+    EXPECT_EQ(result, 5); // Common token found, replace all rightText
+}
+
+TEST_F(LLMSuggestionTest, testCursorWithEqualsSign)
+{
+    // LLM sends code with = and ;
+    int result = LLMSuggestion::calculateReplaceLength("= 5;", ";", "int x;");
+    EXPECT_EQ(result, 1); // Structural overlap on ;
+}
+
+// Edge cases
+TEST_F(LLMSuggestionTest, testNoStructuralButHasToken)
+{
+    // Token overlap but no structural
+    int result = LLMSuggestion::calculateReplaceLength("myVar", "myVariable", "int myVariable");
+    EXPECT_EQ(result, 0); // No structural overlap, tokens too different (length > 1 check)
+}
+
+TEST_F(LLMSuggestionTest, testOnlyWhitespace)
+{
+    // rightText is just whitespace, but "code" is common token
+    int result = LLMSuggestion::calculateReplaceLength("code", "   ", "code   ");
+    EXPECT_EQ(result, 3); // Common token "code", replace rightText
+}
+
+TEST_F(LLMSuggestionTest, testSingleCharTokenIgnored)
+{
+    // Tokens must be > 1 character
+    int result = LLMSuggestion::calculateReplaceLength("a", "b", "ab");
+    EXPECT_EQ(result, 0); // Single char tokens ignored
+}
+
+#include "LLMSuggestionTest.moc"