chore(common): add unit test script for ci

Author: nickchecan

Makefile

@@ -6,24 +6,12 @@ ROOT_DIR := $(CURDIR)
 BUILDPACK_DIR := $(ROOT_DIR)
 PYTHON_BIN ?= python3
 
-.PHONY: test-buildpack clean-test-buildpack test-detect test-compile test-release smoke-test start-local
+.PHONY: test-buildpack clean-test-buildpack test-unit test-detect test-compile test-release smoke-test start-local
 
 # Reset the temporary staging directories used for local buildpack testing.
 clean-test-buildpack:
 	rm -rf $(BUILD_DIR) $(CACHE_DIR) $(ENV_DIR)
 
-# Run unit tests for the detect script without requiring external test tooling.
-test-detect:
-	@bash ./test/unit/detect_test.sh
-
-# Run unit tests for the compile script with stubbed python and uv commands.
-test-compile:
-	@bash ./test/unit/compile_test.sh
-
-# Run unit tests for the release script command-resolution logic.
-test-release:
-	@bash ./test/unit/release_test.sh
-
 # Run the sample app through detect, compile, and release using the same
 # temporary directories each time so local testing is repeatable.
 test-buildpack: clean-test-buildpack
@@ -36,10 +24,6 @@ test-buildpack: clean-test-buildpack
 	cd $(BUILD_DIR) && /bin/bash -lc 'source .profile.d/python.sh && $(PYTHON_BIN) -c "import fastapi; print(fastapi.__version__)"'
 	cd $(BUILD_DIR) && $(BUILDPACK_DIR)/bin/release
 
-# Run the single-app smoke test target against every app fixture under test/smoke.
-smoke-test:
-	@./scripts/smoke-test.sh
-
 # Start the staged sample app locally using the dependencies prepared by `test-buildpack`.
 start-local:
 	@cd $(BUILD_DIR) && /bin/bash -lc '\
@@ -57,3 +41,11 @@ start-local:
 		# Local machines often expose `python3` instead of `python`, so normalize that here. \
 		WEB_CMD=$$(printf "%s" "$$WEB_CMD" | sed "s/^python /$(PYTHON_BIN) /"); \
 		eval "$$WEB_CMD"'
+
+# Run the single-app smoke test target against every app fixture under test/smoke.
+smoke-test:
+	@./scripts/smoke-test.sh
+
+# Run all lightweight script-level unit tests together.
+unit-test: 
+	@./scripts/unit-test.sh

README.md

@@ -2,6 +2,8 @@
 
 The current cloud foundry [python-buildpack](https://github.com/cloudfoundry/python-buildpack) doesn't support modern python tools, such as [uv](https://docs.astral.sh/uv/), so I created this custom buildpack to bridge the gap.
 
+## Installation
+
 ## Testing Locally
 
 Run the buildpack test flow from the repository root:

scripts/unit-test.sh

@@ -0,0 +1,26 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+UNIT_TEST_DIR="${UNIT_TEST_DIR:-$ROOT_DIR/test/unit}"
+
+if [ ! -d "$UNIT_TEST_DIR" ]; then
+  echo "Unit test directory not found: $UNIT_TEST_DIR"
+  exit 1
+fi
+
+found_test=0
+
+# Run every shell test in test/unit and stop immediately if one fails.
+for test_file in "$UNIT_TEST_DIR"/*.sh; do
+  [ -f "$test_file" ] || continue
+  found_test=1
+  echo "==> Running $(basename "$test_file")"
+  bash "$test_file"
+done
+
+if [ "$found_test" -eq 0 ]; then
+  echo "No unit test scripts found in $UNIT_TEST_DIR"
+  exit 1
+fi