Improve scenario update script (#759)

Following #757, improves the script for generating scenario test cases
with:

- A requirements file
- Support for downloading packse scenarios from GitHub dynamically
- Running rustfmt on the generated test file
- Updating snapshots / running tests

crates/puffin-cli/tests/pip_install_scenarios.rs

@@ -1,6 +1,6 @@
 #![cfg(all(feature = "python", feature = "pypi"))]
 
-/// Generated by `scripts/scenarios/generate.py`
+/// Generated by `./scripts/scenarios/update.py`
 use std::process::Command;
 
 use anyhow::Result;

scripts/scenarios/generate.py

@@ -1,56 +0,0 @@
-#!/usr/bin/env python3
-#
-# Generates snapshot test cases from packse scenarios.
-#
-# Usage:
-#     $ scripts/scenarios/generate.py > crates/puffin-cli/tests/pip_install_scenarios.rs
-
-try:
-    import packse
-except ImportError:
-    print("packse must be installed")
-    exit(1)
-
-
-try:
-    import chevron_blue
-except ImportError:
-    print("chevron-blue must be installed")
-    exit(1)
-
-
-import sys
-import subprocess
-import json
-from pathlib import Path
-
-__dir__ = Path(__file__).parent
-
-TEMPLATE = __dir__ / "template.mustache"
-DATA = __dir__ / "data.json"
-
-data = json.loads(
-    subprocess.check_output(
-        [
-            "packse",
-            "inspect",
-            str(packse.__development_base_path__ / "scenarios"),
-        ],
-    )
-)
-
-# Add a generated
-data["generated_by"] = f"Generated by `{' '.join(sys.argv)}`"
-
-# Add normalized names for tests
-for scenario in data["scenarios"]:
-    scenario["normalized_name"] = scenario["name"].replace("-", "_")
-
-# Drop the example scenario
-for index, scenario in enumerate(data["scenarios"]):
-    if scenario["name"] == "example":
-        data["scenarios"].pop(index)
-
-output = chevron_blue.render(template=TEMPLATE.read_text(), data=data, no_escape=True)
-
-print(output)

scripts/scenarios/requirements.txt

@@ -0,0 +1,2 @@
+chevron-blue==0.2.1
+packse @ git+https://github.com/zanieb/packse

scripts/scenarios/update.py

@@ -0,0 +1,143 @@
+#!/usr/bin/env python3
+#
+# Generates and updates snapshot test cases from packse scenarios.
+#
+# Usage:
+#
+#     $ scripts/scenarios/update.py
+#
+# Requirements:
+#
+#   Requires `packse` and `chevron-blue`.
+#
+#     $ pip install -r scripts/scenarios/requirements.txt
+#
+#   Also supports a local, editable requirement on `packse`.
+#
+#   Uses `git`, `rustfmt`, and `cargo insta test` requirements from the project.
+
+import json
+import shutil
+import subprocess
+import sys
+from pathlib import Path
+
+TOOL_ROOT = Path(__file__).parent
+TEMPLATE = TOOL_ROOT / "template.mustache"
+PACKSE = TOOL_ROOT / "packse-scenarios"
+REQUIREMENTS = TOOL_ROOT / "requirements.txt"
+PROJECT_ROOT = TOOL_ROOT.parent.parent
+TARGET = PROJECT_ROOT / "crates" / "puffin-cli" / "tests" / "pip_install_scenarios.rs"
+
+try:
+    import packse
+except ImportError:
+    print(
+        f"missing requirement `packse`: install the requirements at {REQUIREMENTS.relative_to(PROJECT_ROOT)}",
+        file=sys.stderr,
+    )
+    exit(1)
+
+
+try:
+    import chevron_blue
+except ImportError:
+    print(
+        f"missing requirement `chevron-blue`: install the requirements at {REQUIREMENTS.relative_to(PROJECT_ROOT)}",
+        file=sys.stderr,
+    )
+    exit(1)
+
+
+if packse.__development_base_path__.name != "packse":
+    # Not a local editable installation, download latest scenarios
+    if PACKSE.exists():
+        shutil.rmtree(PACKSE)
+
+    print("Downloading scenarios from packse repository...", file=sys.stderr)
+    # Perform a sparse checkout where we only grab the `scenarios` folder
+    subprocess.check_call(
+        [
+            "git",
+            "clone",
+            "-n",
+            "--depth=1",
+            "--filter=tree:0",
+            "https://github.com/zanieb/packse",
+            str(PACKSE),
+        ],
+        cwd=TOOL_ROOT,
+        stdout=subprocess.DEVNULL,
+        stderr=subprocess.STDOUT,
+    )
+    subprocess.check_call(
+        ["git", "sparse-checkout", "set", "--no-cone", "scenarios"],
+        cwd=PACKSE,
+        stdout=subprocess.DEVNULL,
+        stderr=subprocess.STDOUT,
+    )
+    subprocess.check_call(
+        ["git", "checkout"],
+        cwd=PACKSE,
+        stdout=subprocess.DEVNULL,
+        stderr=subprocess.STDOUT,
+    )
+    scenarios_path = str(PACKSE / "scenarios")
+else:
+    print("Using local packse scenarios...", file=sys.stderr)
+    scenarios_path = str(packse.__development_base_path__ / "scenarios")
+
+
+print("Loading scenario metadata...", file=sys.stderr)
+data = json.loads(
+    subprocess.check_output(
+        [
+            "packse",
+            "inspect",
+            scenarios_path,
+        ],
+    )
+)
+
+# Add a generated note
+data["generated_by"] = f"Generated by `{' '.join(sys.argv)}`"
+
+# Add normalized names for tests
+for scenario in data["scenarios"]:
+    scenario["normalized_name"] = scenario["name"].replace("-", "_")
+
+# Drop the example scenario
+for index, scenario in enumerate(data["scenarios"]):
+    if scenario["name"] == "example":
+        data["scenarios"].pop(index)
+
+# Render the template
+print("Rendering template...", file=sys.stderr)
+output = chevron_blue.render(template=TEMPLATE.read_text(), data=data, no_escape=True)
+
+# Update the test file
+print(f"Updating test file at `{TARGET.relative_to(PROJECT_ROOT)}`...", file=sys.stderr)
+with open(TARGET, "wt") as target_file:
+    target_file.write(output)
+
+# Format
+print("Formatting test file...", file=sys.stderr)
+subprocess.check_call(["rustfmt", str(TARGET)])
+
+# Update snapshots
+print("Updating snapshots...\n", file=sys.stderr)
+subprocess.call(
+    [
+        "cargo",
+        "insta",
+        "test",
+        "--accept",
+        "--test",
+        TARGET.with_suffix("").name,
+        "--features",
+        "pypi,python",
+    ],
+    cwd=PROJECT_ROOT,
+)
+
+print("\nDone!", file=sys.stderr)