Eliminate special-casing from test CI workflows. (#9562)

The previous approach was relying on `_test.yml` taking an input
parameter, and then doing almost completely orthogonal things for each
parameter value. I've separated out each of those test situations as its
own job or workflow file, which eliminated all the special-casing and,
in my opinion, improved maintainability by making it much more obvious
what code runs when.

.github/workflows/_pydantic_compatibility.yml

@@ -0,0 +1,76 @@
+name: pydantic v1/v2 compatibility
+
+on:
+  workflow_call:
+    inputs:
+      working-directory:
+        required: true
+        type: string
+        description: "From which folder this pipeline executes"
+
+env:
+  POETRY_VERSION: "1.5.1"
+
+jobs:
+  build:
+    defaults:
+      run:
+        working-directory: ${{ inputs.working-directory }}
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python-version:
+          - "3.8"
+          - "3.9"
+          - "3.10"
+          - "3.11"
+    name: Pydantic v1/v2 compatibility - Python ${{ matrix.python-version }}
+    steps:
+      - uses: actions/checkout@v3
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: "./.github/actions/poetry_setup"
+        with:
+          python-version: ${{ matrix.python-version }}
+          working-directory: ${{ inputs.working-directory }}
+          poetry-version: ${{ env.POETRY_VERSION }}
+          cache-key: pydantic-cross-compat
+          install-command: poetry install
+      - name: Install the opposite major version of pydantic
+        # If normal tests use pydantic v1, here we'll use v2, and vice versa.
+        shell: bash
+        run: |
+          # Determine the major part of pydantic version
+          REGULAR_VERSION=$(poetry run python -c "import pydantic; print(pydantic.__version__)" | cut -d. -f1)
+
+          if [[ "$REGULAR_VERSION" == "1" ]]; then
+            PYDANTIC_DEP=">=2.1,<3"
+            TEST_WITH_VERSION="2"
+          elif [[ "$REGULAR_VERSION" == "2" ]]; then
+            PYDANTIC_DEP="<2"
+            TEST_WITH_VERSION="1"
+          else
+            echo "Unexpected pydantic major version '$REGULAR_VERSION', cannot determine which version to use for cross-compatibility test."
+            exit 1
+          fi
+
+          # Install via `pip` instead of `poetry add` to avoid changing lockfile,
+          # which would prevent caching from working: the cache would get saved
+          # to a different key than where it gets loaded from.
+          poetry run pip install "pydantic${PYDANTIC_DEP}"
+
+          # Ensure that the correct pydantic is installed now.
+          echo "Checking pydantic version... Expecting ${TEST_WITH_VERSION}"
+
+          # Determine the major part of pydantic version
+          CURRENT_VERSION=$(poetry run python -c "import pydantic; print(pydantic.__version__)" | cut -d. -f1)
+
+          # Check that the major part of pydantic version is as expected, if not
+          # raise an error
+          if [[ "$CURRENT_VERSION" != "$TEST_WITH_VERSION" ]]; then
+            echo "Error: expected pydantic version ${CURRENT_VERSION} to have been installed, but found: ${TEST_WITH_VERSION}"
+            exit 1
+          fi
+          echo "Found pydantic version ${CURRENT_VERSION}, as expected"
+      - name: Run pydantic compatibility tests
+        shell: bash
+        run: make test

.github/workflows/_test.yml

@@ -7,10 +7,6 @@ on:
         required: true
         type: string
         description: "From which folder this pipeline executes"
-      test_type:
-        type: string
-        description: "Test types to run"
-        default: '["core", "extended", "core-pydantic-2"]'
 
 env:
   POETRY_VERSION: "1.5.1"
@@ -28,8 +24,7 @@ jobs:
           - "3.9"
           - "3.10"
           - "3.11"
-        test_type: ${{ fromJSON(inputs.test_type) }}
-    name: Python ${{ matrix.python-version }} ${{ matrix.test_type }}
+    name: Python ${{ matrix.python-version }}
     steps:
       - uses: actions/checkout@v3
       - name: Set up Python ${{ matrix.python-version }}
@@ -38,51 +33,8 @@ jobs:
           python-version: ${{ matrix.python-version }}
           working-directory: ${{ inputs.working-directory }}
           poetry-version: ${{ env.POETRY_VERSION }}
-          cache-key: ${{ matrix.test_type }}
-          install-command: |
-              if [ "${{ matrix.test_type }}" == "core" ]; then
-                echo "Running core tests, installing dependencies with poetry..."
-                poetry install
-              elif [ "${{ matrix.test_type }}" == "core-pydantic-2" ]; then
-                echo "Running core-pydantic-v2 tests, installing dependencies with poetry..."
-                poetry install
-
-                # Install via `pip` instead of `poetry add` to avoid changing lockfile,
-                # which would prevent caching from working: the cache would get saved
-                # to a different key than where it gets loaded from.
-                poetry run pip install 'pydantic>=2.1,<3'
-              else
-                echo "Running extended tests, installing dependencies with poetry..."
-                poetry install -E extended_testing
-              fi
-      - name: Verify pydantic version
-        run: |
-          if [ "${{ matrix.test_type }}" == "core-pydantic-2" ]; then
-            EXPECTED_VERSION=2
-          else
-            EXPECTED_VERSION=1
-          fi
-          echo "Checking pydantic version... Expecting ${EXPECTED_VERSION}"
-
-          # Determine the major part of pydantic version
-          VERSION=$(poetry run python -c "import pydantic; print(pydantic.__version__)" | cut -d. -f1)
-
-          # Check that the major part of pydantic version is as expected, if not
-          # raise an error
-          if [[ "$VERSION" -ne $EXPECTED_VERSION ]]; then
-            echo "Error: pydantic version must be equal to ${EXPECTED_VERSION}; Found: ${VERSION}"
-            exit 1
-          fi
-          echo "Found pydantic version ${VERSION}, as expected"
-        shell: bash
-      - name: Run ${{matrix.test_type}} tests
-        run: |
-          case "${{ matrix.test_type }}" in
-              core | core-pydantic-2)
-                  make test
-                  ;;
-              *)
-                  make extended_tests
-                  ;;
-          esac
+          cache-key: core
+          install-command: poetry install
+      - name: Run core tests
         shell: bash
+        run: make test

.github/workflows/langchain_ci.yml

@@ -8,10 +8,15 @@ on:
     paths:
       - '.github/workflows/_lint.yml'
       - '.github/workflows/_test.yml'
+      - '.github/workflows/_pydantic_compatibility.yml'
       - '.github/workflows/langchain_ci.yml'
       - 'libs/langchain/**'
   workflow_dispatch:  # Allows to trigger the workflow manually in GitHub UI
 
+env:
+  POETRY_VERSION: "1.5.1"
+  WORKDIR: "libs/langchain"
+
 jobs:
   lint:
     uses:
@@ -19,10 +24,45 @@ jobs:
     with:
       working-directory: libs/langchain
     secrets: inherit
+
   test:
     uses:
       ./.github/workflows/_test.yml
     with:
       working-directory: libs/langchain
-      test_type: '["core", "extended", "core-pydantic-2"]'
-    secrets: inherit
+    secrets: inherit
+
+  pydantic-compatibility:
+    uses:
+      ./.github/workflows/_pydantic_compatibility.yml
+    with:
+      working-directory: libs/langchain
+    secrets: inherit
+
+  extended-tests:
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: ${{ env.WORKDIR }}
+    strategy:
+      matrix:
+        python-version:
+          - "3.8"
+          - "3.9"
+          - "3.10"
+          - "3.11"
+    name: Python ${{ matrix.python-version }} extended tests
+    steps:
+      - uses: actions/checkout@v3
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: "./.github/actions/poetry_setup"
+        with:
+          python-version: ${{ matrix.python-version }}
+          working-directory: ${{ env.WORKDIR }}
+          poetry-version: ${{ env.POETRY_VERSION }}
+          cache-key: extended
+          install-command: |
+            echo "Running extended tests, installing dependencies with poetry..."
+            poetry install -E extended_testing
+      - name: Run extended tests
+        run: make extended_tests

.github/workflows/langchain_experimental_ci.yml

@@ -25,5 +25,4 @@ jobs:
       ./.github/workflows/_test.yml
     with:
       working-directory: libs/experimental
-      test_type: '["core"]'
-    secrets: inherit
+    secrets: inherit