[Frontend-go] Add unit test for golang

src/fuzz_introspector/frontends/frontend_go.py

@@ -290,13 +290,11 @@ def extract_calltree(self,
         if not func:
             return line_to_print
 
-        callsites = func.base_callsites()
-
         if function in visited_functions:
             return line_to_print
 
         visited_functions.add(function)
-        for cs, line_number in callsites:
+        for cs, line_number in func.base_callsites():
             line_to_print += self.extract_calltree(
                 source_code.source_file,
                 function=cs,
@@ -305,6 +303,43 @@ def extract_calltree(self,
                 line_number=line_number)
         return line_to_print
 
+    def get_reachable_functions(
+            self,
+            source_file: str,
+            source_code: Optional[SourceCodeFile] = None,
+            function: Optional[str] = None,
+            visited_functions: Optional[set[str]] = None) -> set[str]:
+        """Get a list of reachable functions for a provided function name."""
+        if not visited_functions:
+            visited_functions = set()
+
+        if not function and source_code:
+            function = source_code.get_entry_function_name()
+
+        if not function:
+            return visited_functions
+
+        if not source_code and function:
+            source_code = self.find_source_with_func_def(function)
+
+        if not source_code:
+            visited_functions.add(function)
+            return visited_functions
+        print(function)
+        func = source_code.get_function_node(function)
+        if not func or function in visited_functions:
+            visited_functions.add(function)
+            return visited_functions
+
+        visited_functions.add(function)
+        for cs, line_number in func.base_callsites():
+            visited_functions = self.get_reachable_functions(
+                source_code.source_file,
+                function=cs,
+                visited_functions=visited_functions)
+
+        return visited_functions
+
     def find_source_with_func_def(
             self, target_function_name: str) -> Optional[SourceCodeFile]:
         """Finds the source code with a given function."""

src/test/data/source-code/go/test-project-1/fuzzer.go

@@ -0,0 +1,48 @@
+// Copyright 2025 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+package basics
+
+import (
+	"testing"
+	"fmt"
+)
+
+func FuzzBasics(f *testing.F) {
+	f.Fuzz(func(t *testing.T, numString, str, isTrueString string) {
+		num, err := fmt.Sscanf(numString, "%d")
+		if err != nil {
+			return
+		}
+
+		isTrue := false
+		if isTrueString == "true" {
+			isTrue = true
+		}
+
+		_ = calculate(num, isTrue)
+	})
+}
+
+func calculate(a int, b bool) string {
+	if b {
+		return fmt.Sprintf("Number is: %d", a)
+	}
+	return "Boolean is false"
+}
+
+func unusedFunction() {
+	fmt.Println("This function is never used")
+}

src/test/test_frontends_go.py

@@ -0,0 +1,119 @@
+# Copyright 2025 Fuzz Introspector Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""Unit testing script for the Go frontend"""
+
+from fuzz_introspector.frontends import oss_fuzz  # noqa: E402
+
+
+def test_tree_sitter_go_sample1():
+    project = oss_fuzz.analyse_folder(
+        'go',
+        'src/test/data/source-code/go/test-project-1',
+        dump_output=False,
+    )
+
+    # Project check
+    harness = project.get_source_codes_with_harnesses()
+    assert len(harness) == 1
+
+    functions_reached = project.get_reachable_functions(harness[0].source_file, harness[0])
+
+    # Callsite check
+    assert 'calculate' in functions_reached
+    assert 'fmt.Sprintf' in functions_reached
+    assert 'unusedFunction' not in functions_reached
+
+
+def test_tree_sitter_go_sample2():
+    project = oss_fuzz.analyse_folder(
+        'go',
+        'src/test/data/source-code/go/test-project-2',
+        dump_output=False,
+    )
+
+    # Project check
+    harness = project.get_source_codes_with_harnesses()
+    assert len(harness) == 0
+
+
+def test_tree_sitter_go_sample3():
+    project = oss_fuzz.analyse_folder(
+        'go',
+        'src/test/data/source-code/go/test-project-3',
+        dump_output=False,
+    )
+
+    # Project check
+    harness = project.get_source_codes_with_harnesses()
+    assert len(harness) == 0
+
+
+def test_tree_sitter_go_sample4():
+    project = oss_fuzz.analyse_folder(
+        'go',
+        'src/test/data/source-code/go/test-project-4',
+        dump_output=False,
+    )
+
+    # Project check
+    harness = project.get_source_codes_with_harnesses()
+    assert len(harness) == 0
+
+
+def test_tree_sitter_go_sample5():
+    project = oss_fuzz.analyse_folder(
+        'go',
+        'src/test/data/source-code/go/test-project-5',
+        dump_output=False,
+    )
+
+    # Project check
+    harness = project.get_source_codes_with_harnesses()
+    assert len(harness) == 0
+
+
+def test_tree_sitter_go_sample6():
+    project = oss_fuzz.analyse_folder(
+        'go',
+        'src/test/data/source-code/go/test-project-6',
+        dump_output=False,
+    )
+
+    # Project check
+    harness = project.get_source_codes_with_harnesses()
+    assert len(harness) == 0
+
+
+def test_tree_sitter_go_sample7():
+    project = oss_fuzz.analyse_folder(
+        'go',
+        'src/test/data/source-code/go/test-project-8',
+        dump_output=False,
+    )
+
+    # Project check
+    harness = project.get_source_codes_with_harnesses()
+    assert len(harness) == 0
+
+
+def test_tree_sitter_go_sample8():
+    project = oss_fuzz.analyse_folder(
+        'go',
+        'src/test/data/source-code/go/test-project-8',
+        dump_output=False,
+    )
+
+    # Project check
+    harness = project.get_source_codes_with_harnesses()
+    assert len(harness) == 0