Java: Add integration test for buildless lambda recovery

java/ql/integration-tests/java/lambda-expression-buildless-recovery/DB-CHECK.expected

@@ -0,0 +1,3 @@
+[VALUE_NOT_IN_TYPE] predicate diagnostics(@diagnostic id, string generated_by, int severity, string error_tag, string error_message, string full_error_message, @location_default location): Value -16777184 of field location is not in type @location_default. The value is however in the following types: @diagnostic. Appears in tuple (-16777200,"CodeQL Java extractor",5,"","Failed to traverse method body at /private/var/folders/y2/gcxfwn2j4slfs8cnlt6bzsn40000gn/T/pytest-of-idrissrio/pytest-19/ql/java/ql/integration-tests/java/lambda-expression-buildless-recovery/test/test/Test.java:10:17:10:42","",-16777184)
+[VALUE_NOT_IN_TYPE] predicate diagnostic_for(@diagnostic diagnostic, @compilation compilation, int file_number, int file_number_diagnostic_number): Value -16777188 of field diagnostic is not in type @diagnostic. Appears in tuple (-16777188,-16777216,0,14)
+[VALUE_NOT_IN_TYPE] predicate diagnostic_for(@diagnostic diagnostic, @compilation compilation, int file_number, int file_number_diagnostic_number): Value -16777176 of field diagnostic is not in type @diagnostic. Appears in tuple (-16777176,-16777216,0,21)

java/ql/integration-tests/java/lambda-expression-buildless-recovery/ExtractionErrors.expected

@@ -0,0 +1,3 @@
+| Frontend errors in file:  (2 errors during annotation processing) | 2 |
+| Frontend errors in file: Test.java (7 javac errors) | 2 |
+| Unknown errors in file: Test.java (5) | 2 |

java/ql/integration-tests/java/lambda-expression-buildless-recovery/ExtractionErrors.qlref

@@ -0,0 +1 @@
+Diagnostics/ExtractionErrors.ql

java/ql/integration-tests/java/lambda-expression-buildless-recovery/Test.java

@@ -0,0 +1,35 @@
+// The import below is intentionally commented out to test buildless recovery.
+// import java.util.stream.Stream;
+
+public class LambdaBuildlessRecoveryTest {
+
+    private Stream<String> getStringStream() {
+        return getStringStream();
+    }
+
+    public void testSimpleLambdaExpression() {
+        int unused = 0;
+        Stream<String> s = getStringStream();
+        Stream<String> mapped = s.map(x -> x);
+        mapped.forEach(System.out::println);
+    }
+
+    public void testLambdaWithBlockBody() {
+        int unused = 42;
+        Stream<String> s = getStringStream();
+        Stream<String> filtered = s.filter(item -> {
+            int unused = 42;
+            String proc = item.toUpperCase();
+            return proc.length() > 0;
+        });
+        filtered.forEach(System.out::println);
+    }
+
+    public void testVariableCapture() {
+        int unused = 99;
+        String prefix = "proc_";
+        Stream<String> s = getStringStream();
+        Stream<String> result = s.map(item -> prefix + item);
+        result.forEach(System.out::println);
+    }
+}

java/ql/integration-tests/java/lambda-expression-buildless-recovery/test.py

@@ -0,0 +1,5 @@
+def test(codeql, java, use_java_17):
+    codeql.database.create(
+        build_mode="none",
+        source_root="."
+    )

java/ql/integration-tests/java/lambda-expression-buildless-recovery/unused_variable.expected

@@ -0,0 +1,7 @@
+| Test.java:11:9:11:23 | int unused |
+| Test.java:13:9:13:46 | Stream<String> mapped |
+| Test.java:18:9:18:24 | int unused |
+| Test.java:20:9:24:11 | Stream<String> filtered |
+| Test.java:29:9:29:24 | int unused |
+| Test.java:30:9:30:32 | String prefix |
+| Test.java:32:9:32:61 | Stream<String> result |

java/ql/integration-tests/java/lambda-expression-buildless-recovery/unused_variable.ql

@@ -0,0 +1,5 @@
+import java
+
+from LocalVariableDecl v
+where not exists(v.getAnAccess()) and exists(v.getFile().getRelativePath())
+select v