[ty] Enable return type inference in scripts and tools (#29439)

## Summary

Enable return type inference for all 24 standalone Python scripts
checked by ty in CI, along with `py-fuzzer` and `ty_benchmark`.

scripts/add_plugin.py

@@ -4,6 +4,9 @@
 # requires-python = ">=3.12"
 # dependencies = []
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/add_rule.py

@@ -4,6 +4,9 @@
 # requires-python = ">=3.12"
 # dependencies = []
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/build_ruff_pgo.py

@@ -4,6 +4,9 @@
 # requires-python = ">=3.11"
 # dependencies = []
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/bump-workspace-crate-versions.py

@@ -9,6 +9,9 @@
 # requires-python = ">=3.13"
 # dependencies = []
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/check-cargo-bans.py

@@ -2,6 +2,9 @@
 # requires-python = ">=3.12"
 # dependencies = []
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/check-scripts.py

@@ -6,6 +6,9 @@
 #     "pathspec>=1.1.1",
 # ]
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/check_docs_formatted.py

@@ -4,6 +4,9 @@
 # requires-python = ">=3.12"
 # dependencies = ["ruff"]
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/collect_ty_ecosystem_run_metadata.py

@@ -4,6 +4,9 @@
 # requires-python = ">=3.11"
 # dependencies = []
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/conformance.py

@@ -2,6 +2,9 @@
 # requires-python = ">=3.12"
 # dependencies = []
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/ecosystem_all_check.py

@@ -2,6 +2,9 @@
 # requires-python = ">=3.12"
 # dependencies = ["tqdm"]
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/generate-crate-readmes.py

@@ -2,6 +2,9 @@
 # requires-python = ">=3.13"
 # dependencies = []
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/generate_builtin_modules.py

@@ -2,6 +2,9 @@
 # requires-python = ">=3.12"
 # dependencies = []
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/generate_known_standard_library.py

@@ -2,6 +2,9 @@
 # requires-python = ">=3.12"
 # dependencies = ["stdlibs"]
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/generate_mkdocs.py

@@ -6,6 +6,9 @@
 #     "pyyaml>=6.0.3",
 # ]
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/memory_report.py

@@ -2,6 +2,9 @@
 # requires-python = ">=3.12"
 # dependencies = []
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/patch-dist-manifest-checksums.py

@@ -2,6 +2,9 @@
 # requires-python = ">=3.10"
 # dependencies = []
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/publish-crates.py

@@ -2,6 +2,9 @@
 # requires-python = ">=3.12"
 # dependencies = []
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/run_ty_ecosystem_repro.py

@@ -3,6 +3,9 @@
 # requires-python = ">=3.11"
 # dependencies = []
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/setup_primer_project.py

@@ -4,6 +4,9 @@
 # requires-python = ">=3.11"
 # dependencies = ["mypy-primer"]
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/transform_readme.py

@@ -2,6 +2,9 @@
 # requires-python = ">=3.12"
 # dependencies = []
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/ty_benchmark/pyproject.toml

@@ -28,6 +28,9 @@ ignore = [
     "E501", # We use ruff format
 ]
 
+[tool.ty.analysis]
+return-type-inference = "always"
+
 [tool.ty.rules]
 blanket-ignore-comment = "error"
 missing-type-argument = "error"

scripts/update_ambiguous_characters.py

@@ -2,6 +2,9 @@
 # requires-python = ">=3.13"
 # dependencies = []
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"

scripts/update_schemastore.py

@@ -2,6 +2,9 @@
 # requires-python = ">=3.12"
 # dependencies = []
 #
+# [tool.ty.analysis]
+# return-type-inference = "always"
+#
 # [tool.ty.rules]
 # truthiness-test-of-none-union = "warn"
 # blanket-ignore-comment = "warn"