interrogate: explain yourself

Interrogate a codebase for docstring coverage.

Why Do I Need This?

interrogate checks your code base for missing docstrings.

Documentation should be as important as code itself. And it should live within code. Python standardized docstrings, allowing for developers to navigate libraries as simply as calling help() on objects, and with powerful tools like Sphinx, pydoc, and Docutils to automatically generate HTML, LaTeX, PDFs, etc.

Enter: interrogate.

interrogate will tell you which methods, functions, classes, and modules have docstrings, and which do not. Use interrogate to:

  • Get an understanding of how well your code is documented;
  • Add it to CI/CD checks to enforce documentation on newly-added code;
  • Assess a new code base for (one aspect of) code quality and maintainability.

Let’s get started.

Requirements

interrogate supports Python 3.6 and above.

Installation

interrogate is available on PyPI and GitHub. The recommended installation method is pip-installing into a virtualenv:

$ pip install interrogate

Extras

interrogate provides a way to generate a shields.io-like coverage badge as an SVG file. To generate a PNG file instead, install interrogate with the extras [png]:

$ pip install interrogate[png]

NOTICE: Additional system libraries/tools may be required in order to generate a PNG file of the coverage badge:

  • on Windows, install Visual C++ compiler for Cairo;
  • on macOS, install cairo and libffi (with Homebrew for example);
  • on Linux, install the cairo, python3-dev and libffi-dev packages (names may vary depending on distribution).

Refer to the cairosvg documentation for more information.

Usage

Try it out on a Python project:

$ interrogate [PATH]
RESULT: PASSED (minimum: 80.0%, actual: 100.0%)

Add verbosity to see a summary:

$ interrogate -v [PATH]

================== Coverage for /Users/lynn/dev/interrogate/ ====================
------------------------------------ Summary ------------------------------------
| Name                                  |   Total |   Miss |   Cover |   Cover% |
|---------------------------------------|---------|--------|---------|----------|
| src/interrogate/__init__.py           |       1 |      0 |       1 |     100% |
| src/interrogate/__main__.py           |       1 |      0 |       1 |     100% |
| src/interrogate/badge_gen.py          |       6 |      0 |       6 |     100% |
| src/interrogate/cli.py                |       2 |      0 |       2 |     100% |
| src/interrogate/config.py             |       8 |      0 |       8 |     100% |
| src/interrogate/coverage.py           |      27 |      0 |      27 |     100% |
| src/interrogate/utils.py              |      10 |      0 |      10 |     100% |
| src/interrogate/visit.py              |      18 |      0 |      18 |     100% |
| tests/functional/__init__.py          |       1 |      0 |       1 |     100% |
| tests/functional/test_cli.py          |       8 |      0 |       8 |     100% |
| tests/functional/test_coverage.py     |      10 |      0 |      10 |     100% |
| tests/unit/__init__.py                |       1 |      0 |       1 |     100% |
| tests/unit/test_badge_gen.py          |       8 |      0 |       8 |     100% |
| tests/unit/test_config.py             |      10 |      0 |      10 |     100% |
| tests/unit/test_utils.py              |      13 |      0 |      13 |     100% |
|---------------------------------------|---------|--------|---------|----------|
| TOTAL                                 |     124 |      0 |     124 |   100.0% |
---------------- RESULT: PASSED (minimum: 80.0%, actual: 100.0%) ----------------

Add even more verbosity:

$ interrogate -vv [PATH]

================== Coverage for /Users/lynn/dev/interrogate/ ====================
------------------------------- Detailed Coverage -------------------------------
| Name                                                                |  Status |
|---------------------------------------------------------------------|---------|
| src/interrogate/__init__.py (module)                                | COVERED |
|---------------------------------------------------------------------|---------|
| src/interrogate/__main__.py (module)                                | COVERED |
|---------------------------------------------------------------------|---------|
| src/interrogate/badge_gen.py (module)                               | COVERED |
|   save_badge (L42)                                                  | COVERED |
|   get_badge (L87)                                                   | COVERED |
|   should_generate_badge (L103)                                      | COVERED |
|   get_color (L160)                                                  | COVERED |
|   create (L173)                                                     | COVERED |
|---------------------------------------------------------------------|---------|
| src/interrogate/cli.py (module)                                     | COVERED |
|   main (L258)                                                       | COVERED |
|---------------------------------------------------------------------|---------|
| src/interrogate/config.py (module)                                  | COVERED |
|   InterrogateConfig (L19)                                           | COVERED |
|   find_project_root (L61)                                           | COVERED |
|   find_project_config (L89)                                         | COVERED |
|   parse_pyproject_toml (L100)                                       | COVERED |
|   sanitize_list_values (L116)                                       | COVERED |
|   parse_setup_cfg (L139)                                            | COVERED |
|   read_config_file (L173)                                           | COVERED |
|---------------------------------------------------------------------|---------|
| src/interrogate/coverage.py (module)                                | COVERED |
|   BaseInterrogateResult (L23)                                       | COVERED |
|     BaseInterrogateResult.perc_covered (L37)                        | COVERED |
|   InterrogateFileResult (L54)                                       | COVERED |
|     InterrogateFileResult.combine (L67)                             | COVERED |
|   InterrogateResults (L81)                                          | COVERED |
|     InterrogateResults.combine (L93)                                | COVERED |
|   InterrogateCoverage (L101)                                        | COVERED |
|     InterrogateCoverage._add_common_exclude (L121)                  | COVERED |
|     InterrogateCoverage._filter_files (L128)                        | COVERED |
|     InterrogateCoverage.get_filenames_from_paths (L141)             | COVERED |
|     InterrogateCoverage._filter_nodes (L168)                        | COVERED |
|     InterrogateCoverage._filter_inner_nested (L194)                 | COVERED |
|     InterrogateCoverage._get_file_coverage (L203)                   | COVERED |
|     InterrogateCoverage._get_coverage (L231)                        | COVERED |
|     InterrogateCoverage.get_coverage (L248)                         | COVERED |
|     InterrogateCoverage._get_filename (L253)                        | COVERED |
|     InterrogateCoverage._get_detailed_row (L264)                    | COVERED |
|     InterrogateCoverage._create_detailed_table (L281)               | COVERED |
|       InterrogateCoverage._create_detailed_table._sort_nodes (L288) | COVERED |
|     InterrogateCoverage._print_detailed_table (L315)                | COVERED |
|     InterrogateCoverage._create_summary_table (L338)                | COVERED |
|     InterrogateCoverage._print_summary_table (L381)                 | COVERED |
|     InterrogateCoverage._sort_results (L399)                        | COVERED |
|     InterrogateCoverage._get_header_base (L429)                     | COVERED |
|     InterrogateCoverage._print_omitted_file_count (L438)            | COVERED |
|     InterrogateCoverage.print_results (L469)                        | COVERED |
|---------------------------------------------------------------------|---------|
| src/interrogate/utils.py (module)                                   | COVERED |
|   parse_regex (L21)                                                 | COVERED |
|   smart_open (L40)                                                  | COVERED |
|   get_common_base (L60)                                             | COVERED |
|   OutputFormatter (L80)                                             | COVERED |
|     OutputFormatter.should_markup (L90)                             | COVERED |
|     OutputFormatter.set_detailed_markup (L105)                      | COVERED |
|     OutputFormatter.set_summary_markup (L129)                       | COVERED |
|     OutputFormatter._interrogate_line_formatter (L158)              | COVERED |
|     OutputFormatter.get_table_formatter (L226)                      | COVERED |
|---------------------------------------------------------------------|---------|
| src/interrogate/visit.py (module)                                   | COVERED |
|   CovNode (L15)                                                     | COVERED |
|   CoverageVisitor (L44)                                             | COVERED |
|     CoverageVisitor._has_doc (L58)                                  | COVERED |
|     CoverageVisitor._visit_helper (L65)                             | COVERED |
|     CoverageVisitor._is_nested_func (L112)                          | COVERED |
|     CoverageVisitor._is_nested_cls (L121)                           | COVERED |
|     CoverageVisitor._is_private (L133)                              | COVERED |
|     CoverageVisitor._is_semiprivate (L141)                          | COVERED |
|     CoverageVisitor._is_ignored_common (L151)                       | COVERED |
|     CoverageVisitor._has_property_decorators (L168)                 | COVERED |
|     CoverageVisitor._has_setters (L182)                             | COVERED |
|     CoverageVisitor._is_func_ignored (L193)                         | COVERED |
|     CoverageVisitor._is_class_ignored (L217)                        | COVERED |
|     CoverageVisitor.visit_Module (L221)                             | COVERED |
|     CoverageVisitor.visit_ClassDef (L228)                           | COVERED |
|     CoverageVisitor.visit_FunctionDef (L237)                        | COVERED |
|     CoverageVisitor.visit_AsyncFunctionDef (L246)                   | COVERED |
|---------------------------------------------------------------------|---------|
| tests/functional/__init__.py (module)                               | COVERED |
|---------------------------------------------------------------------|---------|
| tests/functional/test_cli.py (module)                               | COVERED |
|   runner (L22)                                                      | COVERED |
|   test_run_no_paths (L30)                                           | COVERED |
|   test_run_shortflags (L77)                                         | COVERED |
|   test_run_longflags (L106)                                         | COVERED |
|   test_run_multiple_flags (L124)                                    | COVERED |
|   test_generate_badge (L135)                                        | COVERED |
|   test_incompatible_options (L170)                                  | COVERED |
|---------------------------------------------------------------------|---------|
| tests/functional/test_coverage.py (module)                          | COVERED |
|   test_coverage_simple (L60)                                        | COVERED |
|   test_coverage_errors (L73)                                        | COVERED |
|   test_print_results (L101)                                         | COVERED |
|   test_print_results_omit_covered (L130)                            | COVERED |
|   test_print_results_omit_none (L156)                               | COVERED |
|   test_print_results_omit_all_summary (L174)                        | COVERED |
|   test_print_results_omit_all_detailed (L198)                       | COVERED |
|   test_print_results_ignore_module (L226)                           | COVERED |
|   test_print_results_single_file (L253)                             | COVERED |
|---------------------------------------------------------------------|---------|
| tests/unit/__init__.py (module)                                     | COVERED |
|---------------------------------------------------------------------|---------|
| tests/unit/test_badge_gen.py (module)                               | COVERED |
|   test_save_badge (L26)                                             | COVERED |
|   test_save_badge_windows (L50)                                     | COVERED |
|   test_save_badge_no_cairo (L62)                                    | COVERED |
|   test_get_badge (L73)                                              | COVERED |
|   test_should_generate (L96)                                        | COVERED |
|   test_get_color (L115)                                             | COVERED |
|   test_create (L136)                                                | COVERED |
|---------------------------------------------------------------------|---------|
| tests/unit/test_config.py (module)                                  | COVERED |
|   test_find_project_root (L29)                                      | COVERED |
|   test_find_project_config (L48)                                    | COVERED |
|   test_parse_pyproject_toml (L57)                                   | COVERED |
|   test_sanitize_list_values (L93)                                   | COVERED |
|   test_parse_setup_cfg (L98)                                        | COVERED |
|   test_parse_setup_cfg_raises (L123)                                | COVERED |
|   test_read_config_file_none (L134)                                 | COVERED |
|   test_read_config_file (L193)                                      | COVERED |
|   test_read_config_file_raises (L207)                               | COVERED |
|---------------------------------------------------------------------|---------|
| tests/unit/test_utils.py (module)                                   | COVERED |
|   test_parse_regex (L32)                                            | COVERED |
|   test_smart_open (L39)                                             | COVERED |
|   test_get_common_base (L69)                                        | COVERED |
|   test_get_common_base_windows (L100)                               | COVERED |
|   test_output_formatter_should_markup (L132)                        | COVERED |
|   test_output_formatter_set_detailed_markup (L163)                  | COVERED |
|   test_output_formatter_set_summary_markup (L206)                   | COVERED |
|   test_output_formatter_interrogate_line_formatter (L258)           | COVERED |
|   test_output_formatter_interrogate_line_formatter_windows (L319)   | COVERED |
|   test_output_formatter_get_table_formatter (L343)                  | COVERED |
|   test_output_formatter_get_table_formatter_py38 (L381)             | COVERED |
|   test_output_formatter_get_table_formatter_raises (L395)           | COVERED |
|---------------------------------------------------------------------|---------|

------------------------------------ Summary ------------------------------------
| Name                                  |   Total |   Miss |   Cover |   Cover% |
|---------------------------------------|---------|--------|---------|----------|
| src/interrogate/__init__.py           |       1 |      0 |       1 |     100% |
| src/interrogate/__main__.py           |       1 |      0 |       1 |     100% |
| src/interrogate/badge_gen.py          |       6 |      0 |       6 |     100% |
| src/interrogate/cli.py                |       2 |      0 |       2 |     100% |
| src/interrogate/config.py             |       8 |      0 |       8 |     100% |
| src/interrogate/coverage.py           |      27 |      0 |      27 |     100% |
| src/interrogate/utils.py              |      10 |      0 |      10 |     100% |
| src/interrogate/visit.py              |      18 |      0 |      18 |     100% |
| tests/functional/__init__.py          |       1 |      0 |       1 |     100% |
| tests/functional/test_cli.py          |       8 |      0 |       8 |     100% |
| tests/functional/test_coverage.py     |      10 |      0 |      10 |     100% |
| tests/unit/__init__.py                |       1 |      0 |       1 |     100% |
| tests/unit/test_badge_gen.py          |       8 |      0 |       8 |     100% |
| tests/unit/test_config.py             |      10 |      0 |      10 |     100% |
| tests/unit/test_utils.py              |      13 |      0 |      13 |     100% |
|---------------------------------------|---------|--------|---------|----------|
| TOTAL                                 |     124 |      0 |     124 |   100.0% |
---------------- RESULT: PASSED (minimum: 80.0%, actual: 100.0%) ----------------

Other Usage

Generate a shields.io badge (like this one! interrogate-badge ):

$ interrogate --generate-badge PATH
RESULT: PASSED (minimum: 80.0%, actual: 100.0%)
Generated badge to /Users/lynn/dev/interrogate/docs/_static/interrogate_badge.svg

See below for more badge configuration.

Add it to your tox.ini file to enforce a level of coverage:

[testenv:doc]
deps = interrogate
skip_install = true
commands =
    interrogate --quiet --fail-under 95 src tests

Or use it with pre-commit:

repos:
  - repo: https://github.com/econchick/interrogate
    rev: 1.5.0  # or master if you're bold
    hooks:
      - id: interrogate
        args: [--quiet, --fail-under=95]

Use it within your code directly:

>>> from interrogate import coverage
>>> cov = coverage.InterrogateCoverage(paths=["src"])
>>> results = cov.get_coverage()
>>> results
InterrogateResults(total=68, covered=65, missing=3)

Use interrogate with GitHub Actions. Check out the action written & maintained by Jack McKew (thank you, Jack!).

Configuration

Configure within your pyproject.toml (interrogate will automatically detect a pyproject.toml file and pick up default values for the command line options):

$ interrogate -c pyproject.toml [OPTIONS] [PATHS]...
[tool.interrogate]
ignore-init-method = true
ignore-init-module = false
ignore-magic = false
ignore-semiprivate = false
ignore-private = false
ignore-property-decorators = false
ignore-module = false
ignore-nested-functions = false
ignore-nested-classes = true
ignore-setters = false
fail-under = 95
exclude = ["setup.py", "docs", "build"]
ignore-regex = ["^get$", "^mock_.*", ".*BaseClass.*"]
# possible values: 0 (minimal output), 1 (-v), 2 (-vv)
verbose = 0
quiet = false
whitelist-regex = []
color = true
omit-covered-files = false
generate-badge = "."
badge-format = "svg"

Or configure within your setup.cfg (interrogate will automatically detect a setup.cfg file and pick up default values for the command line options):

$ interrogate -c setup.cfg [OPTIONS] [PATHS]...
[tool:interrogate]
ignore-init-method = true
ignore-init-module = false
ignore-magic = false
ignore-semiprivate = false
ignore-private = false
ignore-property-decorators = false
ignore-module = false
ignore-nested-functions = false
ignore-nested-classes = true
ignore-setters = false
fail-under = 95
exclude = setup.py,docs,build
ignore-regex = ^get$,^mock_.*,.*BaseClass.*
; possible values: 0 (minimal output), 1 (-v), 2 (-vv)
verbose = 0
quiet = false
whitelist-regex =
color = true
omit-covered-files = false
generate-badge = .
badge-format = svg

Warning

The use of setup.cfg is not recommended unless for very simple use cases. .cfg files use a different parser than pyproject.toml which might cause hard to track down problems. When possible, it is recommended to use pyproject.toml to define your interrogate configuration.

Badge Options

Badge Format

The default file format is svg. Use the --badge-format flag to create a png file instead. Note: interrogate must be installed with interrogate[png] in order to generate png files (see above).

$ interrogate --generate-badge PATH --badge-format png
RESULT: PASSED (minimum: 80.0%, actual: 100.0%)
Generated badge to /Users/lynn/dev/interrogate/docs/_static/interrogate_badge.png

Badge Style

The following badge styles are available via the --badge-style flag:

option example
flat flat-example
flat-square flat-square-example
flat-square-modified (default) interrogate-badge
for-the-badge for-the-badge-example
plastic plastic-example
social social-example

Command Line Options

--version

Show the version and exit.

-v, --verbose

Level of verbosity.

NOTE: When configuring verbosity in pyproject.toml or setup.cfg, verbose=1 maps to -v, and verbose=2 maps to -vv. verbose=0 is the equivalent of no verbose flags used, producing minimal output.

-q, --quiet

Do not print output [default: False]

-f, --fail-under INT | FLOAT

Fail when coverage % is less than a given amount. [default: 80.0]

-e, --exclude PATH

Exclude PATHs of files and/or directories. Multiple -e/--exclude invocations supported.

-i, --ignore-init-method

Ignore __init__ method of classes. [default: False]

-I, --ignore-init-module

Ignore __init__.py modules. [default: False]

-m, --ignore-magic

Ignore all magic methods of classes. [default: False]

NOTE: This does not include the __init__ method. To ignore __init__ methods, use --ignore-init-method.

-M, --ignore-module

Ignore module-level docstrings. [default: False]

-n, --ignore-nested-functions

Ignore nested functions and methods. [default: False]

-C, --ignore-nested-classes

Ignore nested classes. [default: False]

-p, --ignore-private

Ignore private classes, methods, and functions starting with two underscores. [default: False]

NOTE: This does not include magic methods; use --ignore-magic and/or --ignore-init-method instead.

-P, --ignore-property-decorators

Ignore methods with property setter/getter decorators. [default: False]

-S, --ignore-setters

Ignore methods with property setter decorators. [default: False]

-s, --ignore-semiprivate

Ignore semiprivate classes, methods, and functions starting with a single underscore. [default: False]

-r, --ignore-regex STR

Regex identifying class, method, and function names to ignore. Multiple -r/--ignore-regex invocations supported.

-w, --whitelist-regex STR

Regex identifying class, method, and function names to include. Multiple -r/--ignore-regex invocations supported.

-o, --output FILE

Write output to a given FILE. [default: stdout]

-c, --config FILE

Read configuration from pyproject.toml or setup.cfg.

--color, --no-color

Toggle color output on/off when printing to stdout. [default: color]

--omit-covered-files

Omit reporting files that have 100% documentation coverage. This option is ignored if verbosity is not set. [default: False]

-g, --generate-badge PATH

Generate a shields.io status badge (an SVG image) in at a given file or directory. Will not generate a badge if results did not change from an existing badge of the same path.

--badge-format [svg|png]

File format for the generated badge. Used with the -g/--generate-badge flag. [default: svg]

NOTE: To generate a PNG file, interrogate must be installed with interrogate[png], i.e. pip install interrogate[png].

--badge-style [flat|flat-square|flat-square-modified|for-the-badge|plastic|social]

Desired style of shields.io badge. Used with the -g/–generate-badge flag. [default: flat-square-modified]

Credits

interrogate was inspired by docstr-coverage, which was forked from Alexey “DataGreed” Strelkov’s docstring-coverage, which was inspired by a 2004 recipe from James Harlow (turtles…).

The cute sloth logo is by JustineW purchased via the Noun Project (but also available under the Creative Commons License with attribution).

Changelog

1.5.0 (2021-09-10)

Added

  • Set minimum click version (thank you bildzeitung! #81, #82).
  • Add --omit-covered-files flag to skip reporting fully-covered files (#85).
  • Add support for different badge styles via new --badge-style flag (#86).
  • Add 3.10 support!

Fixed

  • Clarify verbose configuration (#83).

1.4.0 (2021-05-14)

Added

  • Support for generating the status badge as a PNG file with a new --badge-format flag (#70).
  • Add new option -C / --ignore-nested-classes to ignore – you guessed it – nested classes (#65).
  • Add new option -S / --ignore-setters to ignore property setter decorators (#68).

1.3.2 (2020-11-03)

Added

  • Add wicked cute Sloth logo to status badge (#48).
  • Testing/support for Python 3.9 – thank you s-weigand!

Fixed

  • Excluding paths are no longer OS-dependent (#51) – thank you oriash93!
  • Include Python trove classifiers in packaging (#61) – thank you mmtj!

Removed

  • Support for Python 3.5 – thank you s-weigand!

1.3.1 (2020-09-03)

Fixed

  • Only generate a status badge if results have changed from an existing badge (#40).

1.3.0 (2020-08-23)

Added

  • Read configuration from pyproject.toml by default (#36).
  • Add -P / --ignore-property-decorators flag to ignore methods with property getter/setter decorators (#37).
  • Add support for read configuration from setup.cfg (#35).

Fixed

  • -e / --exclude doesn’t error if a non-existent file/directory is passed (#38 - thank you MarcoGorelli!).

1.2.0 (2020-05-19)

Added

  • Add -n / --ignore-nested-functions flag to ignore nested functions and methods (#11).
  • Add color output for stdout via --color/--no-color (#25).

Fixed

  • Output now alpha-sorts by directory.

1.1.5 (2020-05-12)

Added

  • Add __main__.py module to allow for invocation via python -m interrogate.

Fixed

  • (Windows) Fix commonpath derivation (#15).
  • (Windows) Fix off-by-1 terminal width error (#20).

Removed

  • Removed networkx dependency.

1.1.4 (2020-05-05)

Added

Fixed

  • Fix summary and detail output to fit width of terminal (thank you psobot!).

1.1.3 (2020-05-02)

Added

  • New -w/--whitelist-regex flag: whitelist regex identifying class, method, and function names to include.

Changed

  • -r/--ignore-regex now supports multiple invocations.

Fixed

  • Fix misleading bug where module info was still outputted even if --ignore-module was used.
  • Fix output when interrogating a single file where filenames were not listed.

1.1.2 (2020-04-29)

Fixed

  • Fix typo in non-quiet results output (thanks hynek!).

Added

  • Add 100% test coverage in the form of functional and unit tests.

1.1.1 (2020-04-27)

Added

  • Improve docstring content to reflect parameters, return values, and raised exceptions.

1.1.0 (2020-04-24)

Added

  • New command to generate a status badge based off of shields.io.

1.0.0.post1 (2020-04-23)

Fixed

  • Add long description to setup.py so PyPI is happy.

1.0.0 (2020-04-23)

Initial release!

Indices and tables