fix(core): handle empty Poetry dev-dependencies (#85)

Running pipelinit in a project with a pyproject.toml
file without a poetry dev-dependencies keys would
crash.

cli/tests/default_test.ts

@@ -65,3 +65,22 @@ test(
     await cleanGitHubFiles("python/requirements-unknown-version");
   },
 );
+
+test(
+  { fixture: "python/requirements-black-and-pyproject", args: [] },
+  async (proc) => {
+    const [stdout, _stderr, { code }] = await output(proc);
+    assertStringIncludes(stdout, "Detected stack: python");
+    assertStringIncludes(
+      stdout,
+      "No linters for python were identified in the project, creating default pipeline with 'flake8' WITHOUT any specific configuration",
+    );
+    assertStringIncludes(
+      stdout,
+      "No formatters for python were identified in the project, creating default pipeline with 'isort' WITHOUT any specific configuration",
+    );
+    assertEquals(code, 0);
+    await assertExpectedFiles("python/requirements-black-and-pyproject");
+    await cleanGitHubFiles("python/requirements-black-and-pyproject");
+  },
+);

cli/tests/fixtures/python/requirements-black-and-pyproject/expected/.github/workflows/pipelinit.python.format.yaml

@@ -0,0 +1,22 @@
+# Generated with pipelinit 0.1.0
+# https://pipelinit.com/
+name: Format Python
+on:
+  pull_request:
+    paths:
+      - "**.py"
+jobs:
+  format:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Set up Python
+        uses: actions/setup-python@v2
+        with:
+          python-version: "3.9"
+      - run: pip install -r requirements.txt
+
+      - run: python -m pip install pip isort
+
+      - run: black . --check
+      - run: isort . -c

cli/tests/fixtures/python/requirements-black-and-pyproject/expected/.github/workflows/pipelinit.python.lint.yaml

@@ -0,0 +1,23 @@
+# Generated with pipelinit 0.1.0
+# https://pipelinit.com/
+name: Lint Python
+on:
+  pull_request:
+    paths:
+      - "**.py"
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Set up Python
+        uses: actions/setup-python@v2
+        with:
+          python-version: "3.9"
+      - run: pip install -r requirements.txt
+
+      - run: python -m pip install pip flake8
+
+      # Adapts Flake8 to run with the Black formatter, using the '--ignore' flag to skip incompatibilities errors
+      # Reference: https://black.readthedocs.io/en/stable/guides/using_black_with_other_tools.html?highlight=other%20tools#id1
+      - run: flake8 --ignore E203,E501,W503 .

cli/tests/fixtures/python/requirements-black-and-pyproject/expected/.github/workflows/pipelinit.python.sast.yaml

@@ -0,0 +1,17 @@
+# Generated with pipelinit 0.1.0
+# https://pipelinit.com/
+name: SAST
+on:
+  pull_request:
+    paths:
+      - "**.py"
+jobs:
+  semgrep:
+    name: Scan
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: returntocorp/semgrep-action@v1
+        with:
+          config: >-
+            p/ci

cli/tests/fixtures/python/requirements-black-and-pyproject/project/.pipelinit.toml

@@ -0,0 +1 @@
+platforms = ["github"]

cli/tests/fixtures/python/requirements-black-and-pyproject/project/.python-version

@@ -0,0 +1 @@
+3.9

cli/tests/fixtures/python/requirements-black-and-pyproject/project/main.py

@@ -0,0 +1 @@
+print("Hello World")

cli/tests/fixtures/python/requirements-black-and-pyproject/project/pyproject.toml

@@ -0,0 +1,2 @@
+[tool.black]
+line-length = 120

cli/tests/fixtures/python/requirements-black-and-pyproject/project/requirements.txt

@@ -0,0 +1 @@
+black==21.9b0

core/plugins/stack/python/dependencies.ts

@@ -10,7 +10,7 @@ const readDependencyFile = async (context: Context) => {
     if (poetryDeps) {
       dependencies.push(...Object.keys(poetryDeps));
     }
-    const poetryDevDeps = pyproject.tool?.poetry["dev-dependencies"];
+    const poetryDevDeps = pyproject.tool?.poetry?.["dev-dependencies"];
     if (poetryDevDeps) {
       dependencies.push(...Object.keys(poetryDevDeps));
     }