Optimize corpus tests: mock downloads, separate data validation, suppress CLI output

.github/workflows/corpus.yml

@@ -0,0 +1,68 @@
+# SPDX-FileCopyrightText: 2026 PyThaiNLP Project
+# SPDX-FileType: SOURCE
+# SPDX-License-Identifier: Apache-2.0
+
+name: Corpus test
+
+on:
+  push:
+    branches:
+      - dev
+    paths:
+      - ".github/workflows/corpus.yml"
+      - "pythainlp/corpus/**"
+      - "tests/corpus/**"
+  pull_request:
+    branches:
+      - dev
+    paths:
+      - ".github/workflows/corpus.yml"
+      - "pythainlp/corpus/**"
+      - "tests/corpus/**"
+
+# Avoid duplicate runs for the same source branch and repository
+concurrency:
+  group: >-
+    ${{ github.workflow }}-${{
+      github.event.pull_request.head.repo.full_name || github.repository
+    }}-${{ github.head_ref || github.ref_name }}
+  cancel-in-progress: true
+
+jobs:
+  corpus:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v6
+
+      - name: Set up Python
+        uses: actions/setup-python@v6
+        with:
+          python-version: "3.13"
+          cache: "pip"
+
+      - name: Install dependencies
+        run: |
+          pip install --upgrade pip
+          pip install .
+
+      - name: Test corpus catalog
+        env:
+          PYTHONIOENCODING: utf-8
+        run: |
+          python -m unittest discover -s tests/corpus -p "test_catalog*.py" -v
+
+      - name: Test built-in corpus files
+        env:
+          PYTHONIOENCODING: utf-8
+        run: |
+          python -m unittest discover -s tests/corpus -p "test_builtin_*.py" -v
+
+      - name: Test downloadable corpus files
+        env:
+          PYTHONIOENCODING: utf-8
+        run: |
+          python -m unittest discover -s tests/corpus -p "test_downloadable_*.py" -v

tests/README.md

@@ -1,3 +1,8 @@
+SPDX-FileCopyrightText: 2026 PyThaiNLP Project
+SPDX-FileType: DOCUMENTATION
+SPDX-License-Identifier: Apache-2.0
+---
+
 # Test suites and execution
 
 To run a test suite, run:
@@ -155,7 +160,6 @@ By separating tests by dependency group, we can:
 - Requires: Internet connection, may involve large downloads
 - Test case class suffix: `TestCaseN`
 
-
 ## Robustness tests (test_robustness.py)
 
 A comprehensive test suite within core tests that tests edge cases important
@@ -169,3 +173,24 @@ for real-world usage:
 - Thai-specific edge cases with combining characters and mixed scripts
 - Multi-engine robustness testing across all core tokenization engines
 - Very long strings that can cause performance issues (issue #893)
+
+## Corpus test (corpus/)
+
+A separate test suite that verifies the integrity, format, parseability,
+and catalog functionality of corpus in PyThaiNLP.
+
+These tests are separate from regular unit tests because they test actual
+file loading and parsing (not mocked), require network access, and
+can be resource intensive.
+
+For detailed information about corpus test, see:
+[tests/corpus/README.md](corpus/README.md)
+
+The corpus test is triggered automatically via GitHub Actions
+when changes are made to `pythainlp/corpus/**` or `tests/corpus/**`.
+
+Run corpus test:
+
+```shell
+python -m unittest tests.corpus
+```