diff --git a/MODULE.bazel b/MODULE.bazel
index e0659ac0..908c7314 100644
--- a/MODULE.bazel
+++ b/MODULE.bazel
@@ -19,6 +19,11 @@ module(name = "rules_codechecker")
 bazel_dep(name = "rules_cc", version = "0.2.3")
 bazel_dep(name = "rules_python", version = "0.38.0")
 
+bazel_dep(
+    name = "bazel_skylib",
+    version = "1.7.1",
+    dev_dependency = True,
+)
 bazel_dep(
     name = "buildifier_prebuilt",
     version = "7.3.1",
diff --git a/test/unit/compile_commands/BUILD b/test/unit/compile_commands/BUILD
new file mode 100644
index 00000000..042f4d1f
--- /dev/null
+++ b/test/unit/compile_commands/BUILD
@@ -0,0 +1,230 @@
+# Copyright 2026 Ericsson AB
+#
+# 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.
+
+load("@rules_cc//cc:defs.bzl", "cc_library")
+load(
+    ":compile_commands_analysis_test.bzl",
+    "custom_ccinfo",
+    "get_compile_flags_defines_from_impl_deps_test",
+    "get_compile_flags_includes_from_impl_deps_test",
+    "get_compile_flags_local_defines_from_impl_deps_test",
+    "get_compile_flags_no_duplicates_test",
+    "get_compile_flags_quote_includes_from_deps_test",
+    "get_compile_flags_system_includes_from_impl_deps_test",
+    "get_compile_flags_test_suite",
+)
+
+# =============================================================================
+# Analysis tests
+# =============================================================================
+
+# get_compile_flags
+# -----------------
+
+cc_library(
+    name = "compile_flags_tests_with_defines",
+    srcs = ["testdata/foo.cc"],
+    hdrs = ["testdata/foo.h"],
+    defines = ["MY_DEFINE=1"],
+    tags = ["manual"],
+)
+
+# BUG (manual): defines from implementation_deps are not collected.
+cc_library(
+    name = "compile_flags_tests_impl_dep_with_defines",
+    srcs = ["testdata/bar.cc"],
+    hdrs = ["testdata/bar.h"],
+    defines = ["IMPL_DEP_DEFINE=1"],
+    tags = ["manual"],
+)
+
+cc_library(
+    name = "compile_flags_tests_with_impl_dep_defines",
+    srcs = ["testdata/foo.cc"],
+    hdrs = ["testdata/foo.h"],
+    implementation_deps = [":compile_flags_tests_impl_dep_with_defines"],
+    tags = ["manual"],
+)
+
+get_compile_flags_defines_from_impl_deps_test(
+    name = "get_compile_flags_defines_from_impl_deps",
+    tags = ["manual"],
+    target_under_test = ":compile_flags_tests_with_impl_dep_defines",
+)
+
+cc_library(
+    name = "compile_flags_tests_with_local_defines",
+    srcs = ["testdata/foo.cc"],
+    hdrs = ["testdata/foo.h"],
+    local_defines = ["LOCAL_DEF=1"],
+    tags = ["manual"],
+)
+
+# BUG (manual): local_defines from implementation_deps are not collected.
+cc_library(
+    name = "compile_flags_tests_impl_dep_with_local_defines",
+    srcs = ["testdata/bar.cc"],
+    hdrs = ["testdata/bar.h"],
+    local_defines = ["IMPL_DEP_LOCAL_DEF=1"],
+    tags = ["manual"],
+)
+
+cc_library(
+    name = "compile_flags_tests_with_impl_dep_local_defines",
+    srcs = ["testdata/foo.cc"],
+    hdrs = ["testdata/foo.h"],
+    implementation_deps = [":compile_flags_tests_impl_dep_with_local_defines"],
+    tags = ["manual"],
+)
+
+get_compile_flags_local_defines_from_impl_deps_test(
+    name = "get_compile_flags_local_defines_from_impl_deps",
+    tags = ["manual"],
+    target_under_test = ":compile_flags_tests_with_impl_dep_local_defines",
+)
+
+cc_library(
+    name = "compile_flags_tests_with_includes",
+    srcs = ["testdata/foo.cc"],
+    hdrs = ["testdata/foo.h"],
+    includes = ["my/include/path"],
+    tags = ["manual"],
+)
+
+# includes from implementation_deps should be collected.
+cc_library(
+    name = "compile_flags_tests_impl_dep_with_includes",
+    srcs = ["testdata/bar.cc"],
+    hdrs = ["testdata/bar.h"],
+    includes = ["impl_dep/include"],
+    tags = ["manual"],
+)
+
+cc_library(
+    name = "compile_flags_tests_with_impl_dep_includes",
+    srcs = ["testdata/foo.cc"],
+    hdrs = ["testdata/foo.h"],
+    implementation_deps = [":compile_flags_tests_impl_dep_with_includes"],
+    tags = ["manual"],
+)
+
+get_compile_flags_includes_from_impl_deps_test(
+    name = "get_compile_flags_includes_from_impl_deps",
+    target_under_test = ":compile_flags_tests_with_impl_dep_includes",
+)
+
+cc_library(
+    name = "compile_flags_tests_with_copts",
+    srcs = ["testdata/foo.cc"],
+    hdrs = ["testdata/foo.h"],
+    copts = [
+        "-Wall",
+        "-Wextra",
+    ],
+    tags = ["manual"],
+)
+
+cc_library(
+    name = "compile_flags_tests_dep_with_includes",
+    srcs = ["testdata/bar.cc"],
+    hdrs = ["testdata/bar.h"],
+    includes = ["dep/include"],
+    tags = ["manual"],
+)
+
+cc_library(
+    name = "compile_flags_tests_with_dep_includes",
+    srcs = ["testdata/foo.cc"],
+    hdrs = ["testdata/foo.h"],
+    tags = ["manual"],
+    deps = [":compile_flags_tests_dep_with_includes"],
+)
+
+custom_ccinfo(
+    name = "compile_flags_tests_sys_include_provider",
+    system_includes = ["my/sys/include"],
+    tags = ["manual"],
+)
+
+cc_library(
+    name = "compile_flags_tests_with_system_includes",
+    srcs = ["testdata/foo.cc"],
+    hdrs = ["testdata/foo.h"],
+    tags = ["manual"],
+    deps = [":compile_flags_tests_sys_include_provider"],
+)
+
+# system_includes from implementation_deps should be collected.
+custom_ccinfo(
+    name = "compile_flags_tests_impl_dep_sys_include_provider",
+    system_includes = ["impl_dep/sys/include"],
+    tags = ["manual"],
+)
+
+cc_library(
+    name = "compile_flags_tests_with_impl_dep_system_includes",
+    srcs = ["testdata/foo.cc"],
+    hdrs = ["testdata/foo.h"],
+    implementation_deps = [":compile_flags_tests_impl_dep_sys_include_provider"],
+    tags = ["manual"],
+)
+
+get_compile_flags_system_includes_from_impl_deps_test(
+    name = "get_compile_flags_system_includes_from_impl_deps",
+    target_under_test = ":compile_flags_tests_with_impl_dep_system_includes",
+)
+
+custom_ccinfo(
+    name = "compile_flags_tests_quote_include_provider",
+    quote_includes = ["my/quote/include"],
+    tags = ["manual"],
+)
+
+cc_library(
+    name = "compile_flags_tests_with_quote_includes",
+    srcs = ["testdata/foo.cc"],
+    hdrs = ["testdata/foo.h"],
+    tags = ["manual"],
+    deps = [":compile_flags_tests_quote_include_provider"],
+)
+
+# BUG (manual): quote_includes from implementation_deps are not collected.
+custom_ccinfo(
+    name = "compile_flags_tests_dep_quote_include_provider",
+    quote_includes = ["dep/quote/path"],
+    tags = ["manual"],
+)
+
+cc_library(
+    name = "compile_flags_tests_with_dep_quote_includes",
+    srcs = ["testdata/foo.cc"],
+    hdrs = ["testdata/foo.h"],
+    implementation_deps = [":compile_flags_tests_dep_quote_include_provider"],
+    tags = ["manual"],
+)
+
+get_compile_flags_quote_includes_from_deps_test(
+    name = "get_compile_flags_quote_includes_from_deps",
+    tags = ["manual"],
+    target_under_test = ":compile_flags_tests_with_dep_quote_includes",
+)
+
+get_compile_flags_test_suite(name = "compile_flags_tests")
+
+# BUG (manual): compile commands should not contain duplicate flags.
+get_compile_flags_no_duplicates_test(
+    name = "get_compile_flags_no_duplicates",
+    tags = ["manual"],
+    target_under_test = ":compile_flags_tests_with_dep_includes",
+)
diff --git a/test/unit/compile_commands/compile_commands_analysis_test.bzl b/test/unit/compile_commands/compile_commands_analysis_test.bzl
new file mode 100644
index 00000000..5c0b1a8a
--- /dev/null
+++ b/test/unit/compile_commands/compile_commands_analysis_test.bzl
@@ -0,0 +1,407 @@
+# Copyright 2026 Ericsson AB
+#
+# 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.
+
+"""
+Analysis-phase tests for compile_commands.bzl.
+
+Tests the following functions indirectly via compile_commands_aspect:
+  - collect_headers
+  - get_sources
+  - get_compile_flags
+  - _cc_compiler_info
+"""
+
+load("@bazel_skylib//lib:unittest.bzl", "analysistest", "asserts")
+load(
+    "//src:compile_commands.bzl",
+    "SourceFilesInfo",
+    "compile_commands_aspect",
+)
+
+# =============================================================================
+# Helper rules
+# =============================================================================
+
+def _custom_ccinfo_impl(ctx):
+    """Rule that provides a CcInfo with custom include paths and defines."""
+    compilation_context = cc_common.create_compilation_context(
+        defines = depset(ctx.attr.defines),
+        system_includes = depset(ctx.attr.system_includes),
+        quote_includes = depset(ctx.attr.quote_includes),
+        includes = depset(ctx.attr.includes),
+    )
+    return [CcInfo(compilation_context = compilation_context)]
+
+custom_ccinfo = rule(
+    implementation = _custom_ccinfo_impl,
+    attrs = {
+        "defines": attr.string_list(default = []),
+        "includes": attr.string_list(default = []),
+        "quote_includes": attr.string_list(default = []),
+        "system_includes": attr.string_list(default = []),
+    },
+)
+
+# =============================================================================
+# Helpers
+# =============================================================================
+
+def _get_compile_commands(source_files_info):
+    """Extract command strings from SourceFilesInfo.compilation_db."""
+    return [entry.command for entry in source_files_info.compilation_db.to_list()]
+
+# =============================================================================
+# get_compile_flags
+# =============================================================================
+
+def _get_compile_flags_defines_test_impl(ctx):
+    """defines appear as -D in the compile command."""
+    env = analysistest.begin(ctx)
+    commands = _get_compile_commands(analysistest.target_under_test(env)[SourceFilesInfo])
+
+    asserts.true(env, len(commands) > 0, "Should have at least one compile command")
+    asserts.true(
+        env,
+        "MY_DEFINE" in commands[0],
+        "Should contain define MY_DEFINE, got: %s" % commands[0],
+    )
+
+    return analysistest.end(env)
+
+get_compile_flags_defines_test = analysistest.make(
+    _get_compile_flags_defines_test_impl,
+    extra_target_under_test_aspects = [compile_commands_aspect],
+)
+
+def _get_compile_flags_defines_from_impl_deps_test_impl(ctx):
+    """BUG: defines from implementation_deps are missing in compile commands.
+
+    get_compile_flags iterates over deps in SOURCE_ATTR and collects includes,
+    system_includes, and external_includes — but NOT defines.
+    """
+    env = analysistest.begin(ctx)
+    commands = _get_compile_commands(analysistest.target_under_test(env)[SourceFilesInfo])
+
+    foo_commands = [c for c in commands if "foo.cc" in c]
+    asserts.true(env, len(foo_commands) > 0, "Should have a command for foo.cc")
+    asserts.true(
+        env,
+        "IMPL_DEP_DEFINE" in foo_commands[0],
+        "Should contain define IMPL_DEP_DEFINE from implementation_dep, got: %s" % foo_commands[0],
+    )
+
+    return analysistest.end(env)
+
+get_compile_flags_defines_from_impl_deps_test = analysistest.make(
+    _get_compile_flags_defines_from_impl_deps_test_impl,
+    extra_target_under_test_aspects = [compile_commands_aspect],
+)
+
+def _get_compile_flags_local_defines_test_impl(ctx):
+    """local_defines appear as -D in the compile command."""
+    env = analysistest.begin(ctx)
+    commands = _get_compile_commands(analysistest.target_under_test(env)[SourceFilesInfo])
+
+    asserts.true(env, len(commands) > 0, "Should have at least one compile command")
+    asserts.true(
+        env,
+        "LOCAL_DEF" in commands[0],
+        "Should contain local_define LOCAL_DEF, got: %s" % commands[0],
+    )
+
+    return analysistest.end(env)
+
+get_compile_flags_local_defines_test = analysistest.make(
+    _get_compile_flags_local_defines_test_impl,
+    extra_target_under_test_aspects = [compile_commands_aspect],
+)
+
+def _get_compile_flags_local_defines_from_impl_deps_test_impl(ctx):
+    """BUG: local_defines from implementation_deps are missing in compile commands.
+
+    get_compile_flags iterates over deps in SOURCE_ATTR and collects includes,
+    system_includes, and external_includes — but NOT local_defines.
+    """
+    env = analysistest.begin(ctx)
+    commands = _get_compile_commands(analysistest.target_under_test(env)[SourceFilesInfo])
+
+    foo_commands = [c for c in commands if "foo.cc" in c]
+    asserts.true(env, len(foo_commands) > 0, "Should have a command for foo.cc")
+    asserts.true(
+        env,
+        "IMPL_DEP_LOCAL_DEF" in foo_commands[0],
+        "Should contain local_define IMPL_DEP_LOCAL_DEF from implementation_dep, got: %s" % foo_commands[0],
+    )
+
+    return analysistest.end(env)
+
+get_compile_flags_local_defines_from_impl_deps_test = analysistest.make(
+    _get_compile_flags_local_defines_from_impl_deps_test_impl,
+    extra_target_under_test_aspects = [compile_commands_aspect],
+)
+
+def _get_compile_flags_includes_test_impl(ctx):
+    """includes appear as -I in the compile command."""
+    env = analysistest.begin(ctx)
+    commands = _get_compile_commands(analysistest.target_under_test(env)[SourceFilesInfo])
+
+    asserts.true(env, len(commands) > 0, "Should have at least one compile command")
+    asserts.true(
+        env,
+        "my/include/path" in commands[0],
+        "Should contain include path, got: %s" % commands[0],
+    )
+
+    return analysistest.end(env)
+
+get_compile_flags_includes_test = analysistest.make(
+    _get_compile_flags_includes_test_impl,
+    extra_target_under_test_aspects = [compile_commands_aspect],
+)
+
+def _get_compile_flags_includes_from_impl_deps_test_impl(ctx):
+    """includes from implementation_deps propagate to the compile command."""
+    env = analysistest.begin(ctx)
+    commands = _get_compile_commands(analysistest.target_under_test(env)[SourceFilesInfo])
+
+    foo_commands = [c for c in commands if "foo.cc" in c]
+    asserts.true(env, len(foo_commands) > 0, "Should have a command for foo.cc")
+    asserts.true(
+        env,
+        "impl_dep/include" in foo_commands[0],
+        "Should contain impl_dep's include path, got: %s" % foo_commands[0],
+    )
+
+    return analysistest.end(env)
+
+get_compile_flags_includes_from_impl_deps_test = analysistest.make(
+    _get_compile_flags_includes_from_impl_deps_test_impl,
+    extra_target_under_test_aspects = [compile_commands_aspect],
+)
+
+def _get_compile_flags_copts_test_impl(ctx):
+    """copts are passed through to the compile command."""
+    env = analysistest.begin(ctx)
+    commands = _get_compile_commands(analysistest.target_under_test(env)[SourceFilesInfo])
+
+    asserts.true(env, len(commands) > 0, "Should have at least one compile command")
+    asserts.true(
+        env,
+        "-Wall" in commands[0],
+        "Should contain -Wall, got: %s" % commands[0],
+    )
+    asserts.true(
+        env,
+        "-Wextra" in commands[0],
+        "Should contain -Wextra, got: %s" % commands[0],
+    )
+
+    return analysistest.end(env)
+
+get_compile_flags_copts_test = analysistest.make(
+    _get_compile_flags_copts_test_impl,
+    extra_target_under_test_aspects = [compile_commands_aspect],
+)
+
+def _get_compile_flags_dep_includes_test_impl(ctx):
+    """includes from deps propagate to the compile command."""
+    env = analysistest.begin(ctx)
+    commands = _get_compile_commands(analysistest.target_under_test(env)[SourceFilesInfo])
+
+    foo_commands = [c for c in commands if "foo.cc" in c]
+    asserts.true(env, len(foo_commands) > 0, "Should have a command for foo.cc")
+    asserts.true(
+        env,
+        "dep/include" in foo_commands[0],
+        "Should contain dep's include path, got: %s" % foo_commands[0],
+    )
+
+    return analysistest.end(env)
+
+get_compile_flags_dep_includes_test = analysistest.make(
+    _get_compile_flags_dep_includes_test_impl,
+    extra_target_under_test_aspects = [compile_commands_aspect],
+)
+
+def _get_compile_flags_system_includes_test_impl(ctx):
+    """system_includes appear as -isystem in the compile command."""
+    env = analysistest.begin(ctx)
+    commands = _get_compile_commands(analysistest.target_under_test(env)[SourceFilesInfo])
+
+    asserts.true(env, len(commands) > 0, "Should have at least one compile command")
+    asserts.true(
+        env,
+        "-isystem my/sys/include" in commands[0],
+        "Should contain -isystem my/sys/include, got: %s" % commands[0],
+    )
+
+    return analysistest.end(env)
+
+get_compile_flags_system_includes_test = analysistest.make(
+    _get_compile_flags_system_includes_test_impl,
+    extra_target_under_test_aspects = [compile_commands_aspect],
+)
+
+def _get_compile_flags_system_includes_from_impl_deps_test_impl(ctx):
+    """system_includes from implementation_deps appear as -isystem in the compile command."""
+    env = analysistest.begin(ctx)
+    commands = _get_compile_commands(analysistest.target_under_test(env)[SourceFilesInfo])
+
+    foo_commands = [c for c in commands if "foo.cc" in c]
+    asserts.true(env, len(foo_commands) > 0, "Should have a command for foo.cc")
+    asserts.true(
+        env,
+        "-isystem impl_dep/sys/include" in foo_commands[0],
+        "Should contain -isystem impl_dep/sys/include from implementation_dep, got: %s" % foo_commands[0],
+    )
+
+    return analysistest.end(env)
+
+get_compile_flags_system_includes_from_impl_deps_test = analysistest.make(
+    _get_compile_flags_system_includes_from_impl_deps_test_impl,
+    extra_target_under_test_aspects = [compile_commands_aspect],
+)
+
+def _get_compile_flags_quote_includes_test_impl(ctx):
+    """quote_includes appear as -iquote in the compile command."""
+    env = analysistest.begin(ctx)
+    commands = _get_compile_commands(analysistest.target_under_test(env)[SourceFilesInfo])
+
+    asserts.true(env, len(commands) > 0, "Should have at least one compile command")
+    asserts.true(
+        env,
+        "-iquote my/quote/include" in commands[0],
+        "Should contain -iquote my/quote/include, got: %s" % commands[0],
+    )
+
+    return analysistest.end(env)
+
+get_compile_flags_quote_includes_test = analysistest.make(
+    _get_compile_flags_quote_includes_test_impl,
+    extra_target_under_test_aspects = [compile_commands_aspect],
+)
+
+def _get_compile_flags_quote_includes_from_deps_test_impl(ctx):
+    """BUG: quote_includes from implementation_deps are missing in compile commands.
+
+    get_compile_flags iterates over deps in SOURCE_ATTR and collects includes,
+    system_includes, and external_includes — but NOT quote_includes.
+    """
+    env = analysistest.begin(ctx)
+    commands = _get_compile_commands(analysistest.target_under_test(env)[SourceFilesInfo])
+
+    foo_commands = [c for c in commands if "foo.cc" in c]
+    asserts.true(env, len(foo_commands) > 0, "Should have a command for foo.cc")
+
+    asserts.true(
+        env,
+        "-iquote dep/quote/path" in foo_commands[0],
+        "Should contain -iquote dep/quote/path from implementation_dep, got: %s" % foo_commands[0],
+    )
+
+    return analysistest.end(env)
+
+get_compile_flags_quote_includes_from_deps_test = analysistest.make(
+    _get_compile_flags_quote_includes_from_deps_test_impl,
+    extra_target_under_test_aspects = [compile_commands_aspect],
+)
+
+def _get_compile_flags_no_duplicates_test_impl(ctx):
+    """BUG: Compile flags should not contain duplicates.
+
+    get_compile_flags may add the same include path multiple times — once
+    from the target's own CcInfo compilation_context, and again when iterating
+    over deps in SOURCE_ATTR. This test asserts the desired behavior:
+    no flag should appear more than once in a compile command.
+    """
+    env = analysistest.begin(ctx)
+    commands = _get_compile_commands(analysistest.target_under_test(env)[SourceFilesInfo])
+
+    foo_commands = [c for c in commands if "foo.cc" in c]
+    asserts.true(env, len(foo_commands) > 0, "Should have a command for foo.cc")
+
+    # Split command into flags and check for duplicates
+    flags = foo_commands[0].split(" ")
+    seen = []
+    duplicates = []
+    for f in flags:
+        if f == "":
+            continue
+        if f in seen and f not in duplicates:
+            duplicates.append(f)
+        seen.append(f)
+    asserts.true(
+        env,
+        len(duplicates) == 0,
+        "Compile command should not have duplicate flags, found: %s" % duplicates,
+    )
+
+    return analysistest.end(env)
+
+get_compile_flags_no_duplicates_test = analysistest.make(
+    _get_compile_flags_no_duplicates_test_impl,
+    extra_target_under_test_aspects = [compile_commands_aspect],
+)
+
+# =============================================================================
+# Test suites
+# =============================================================================
+
+def get_compile_flags_test_suite(name):
+    """Analysis tests for get_compile_flags.
+
+    Args:
+        name: the name prefix for the test suite.
+    """
+    get_compile_flags_defines_test(
+        name = name + "_defines_test",
+        target_under_test = ":" + name + "_with_defines",
+    )
+    get_compile_flags_local_defines_test(
+        name = name + "_local_defines_test",
+        target_under_test = ":" + name + "_with_local_defines",
+    )
+    get_compile_flags_includes_test(
+        name = name + "_includes_test",
+        target_under_test = ":" + name + "_with_includes",
+    )
+    get_compile_flags_copts_test(
+        name = name + "_copts_test",
+        target_under_test = ":" + name + "_with_copts",
+    )
+    get_compile_flags_dep_includes_test(
+        name = name + "_dep_includes_test",
+        target_under_test = ":" + name + "_with_dep_includes",
+    )
+    get_compile_flags_system_includes_test(
+        name = name + "_system_includes_test",
+        target_under_test = ":" + name + "_with_system_includes",
+    )
+    get_compile_flags_quote_includes_test(
+        name = name + "_quote_includes_test",
+        target_under_test = ":" + name + "_with_quote_includes",
+    )
+
+    native.test_suite(
+        name = name,
+        tests = [
+            ":" + name + "_defines_test",
+            ":" + name + "_local_defines_test",
+            ":" + name + "_includes_test",
+            ":" + name + "_copts_test",
+            ":" + name + "_dep_includes_test",
+            ":" + name + "_system_includes_test",
+            ":" + name + "_quote_includes_test",
+        ],
+    )
diff --git a/test/unit/compile_commands/testdata/bar.c b/test/unit/compile_commands/testdata/bar.c
new file mode 100644
index 00000000..e194bebb
--- /dev/null
+++ b/test/unit/compile_commands/testdata/bar.c
@@ -0,0 +1,2 @@
+#include "bar.h"
+void bar(void) {}
diff --git a/test/unit/compile_commands/testdata/bar.cc b/test/unit/compile_commands/testdata/bar.cc
new file mode 100644
index 00000000..e194bebb
--- /dev/null
+++ b/test/unit/compile_commands/testdata/bar.cc
@@ -0,0 +1,2 @@
+#include "bar.h"
+void bar(void) {}
diff --git a/test/unit/compile_commands/testdata/bar.h b/test/unit/compile_commands/testdata/bar.h
new file mode 100644
index 00000000..2f848f6d
--- /dev/null
+++ b/test/unit/compile_commands/testdata/bar.h
@@ -0,0 +1,4 @@
+#ifndef BAR_H
+#define BAR_H
+void bar(void);
+#endif
diff --git a/test/unit/compile_commands/testdata/foo.cc b/test/unit/compile_commands/testdata/foo.cc
new file mode 100644
index 00000000..02ec45e8
--- /dev/null
+++ b/test/unit/compile_commands/testdata/foo.cc
@@ -0,0 +1,2 @@
+#include "foo.h"
+void foo(void) {}
diff --git a/test/unit/compile_commands/testdata/foo.h b/test/unit/compile_commands/testdata/foo.h
new file mode 100644
index 00000000..518642bf
--- /dev/null
+++ b/test/unit/compile_commands/testdata/foo.h
@@ -0,0 +1,4 @@
+#ifndef FOO_H
+#define FOO_H
+void foo(void);
+#endif