pystache 0.6.0

Making Changes & Contributing

This repo is now pre-commit enabled for various linting and format checks (and in many cases, automatic fixes). The checks run on commit/push and will fail the commit (if not clean) with some checks performing simple file corrections. Simply review the changes and adjust (if needed) then git add the files and continue.

If other checks fail on commit, the failure display should explain the error types and line numbers. Note you must fix any fatal errors for the commit to succeed; some errors should be fixed automatically (use git status and git diff to review any changes).

Note pylint is the primary check that requires your own input, as well as a decision as to the appropriate fix action. You must fix any pylint warnings (relative to the baseline config score) for the commit to succeed.

See the pre-commit docs under docs/dev/ for more information.

• pre-commit-config

• pre-commit-usage

You will need to install pre-commit before contributing any changes; installing it using your system’s package manager is recommended, otherwise install with pip into your local user’s virtual environment using something like:

$ sudo emerge pre-commit  --or--
$ pip install pre-commit

then install it into the repo you just cloned:

$ git clone https://github.com/PennyDreadfulMTG/pystache
$ cd pystache
$ pre-commit install
$ pre-commit install-hooks

It’s usually a good idea to update the hooks to the latest version:

pre-commit autoupdate

Requirements

Pystache is tested with–

• Python 3.6

• Python 3.7

• Python 3.8

• Python 3.9

• Conda (py36-py39)

Distribute (the setuptools fork) is no longer required over setuptools, as the current packaging is now PEP517-compliant.

JSON support is needed only for the command-line interface and to run the spec tests; PyYAML can still be used (see the Develop section).

Official support for Python 2 will end with Pystache version 0.6.0.

Install It

pip install -U pystache -f https://github.com/PennyDreadfulMTG/pystache/releases/

And test it:

pystache-test

To install and test from source (e.g. from GitHub), see the Develop section.

Use It

>>> import pystache
>>> print(pystache.render('Hi {{person}}!', {'person': 'Mom'}))
Hi Mom!

You can also create dedicated view classes to hold your view logic.

Here’s your view class (in ../pystache/tests/examples/readme.py):

class SayHello(object):
    def to(self):
        return "Pizza"

Instantiating like so:

>>> from pystache.tests.examples.readme import SayHello
>>> hello = SayHello()

Then your template, say_hello.mustache (by default in the same directory as your class definition):

Hello, {{to}}!

Pull it together:

>>> renderer = pystache.Renderer()
>>> print(renderer.render(hello))
Hello, Pizza!

For greater control over rendering (e.g. to specify a custom template directory), use the Renderer class like above. One can pass attributes to the Renderer class constructor or set them on a Renderer instance. To customize template loading on a per-view basis, subclass TemplateSpec. See the docstrings of the Renderer class and TemplateSpec class for more information.

You can also pre-parse a template:

>>> parsed = pystache.parse(u"Hey {{#who}}{{.}}!{{/who}}")
>>> print(parsed)
['Hey ', _SectionNode(key='who', index_begin=12, index_end=18, parsed=[_EscapeNode(key='.'), '!'])]

And then:

>>> print(renderer.render(parsed, {'who': 'Pops'}))
Hey Pops!
>>> print(renderer.render(parsed, {'who': 'you'}))
Hey you!

Unicode

This section describes how Pystache handles unicode, strings, and encodings.

Internally, Pystache uses only unicode strings. For input, Pystache accepts both unicode strings and byte strings. For output, Pystache’s template rendering methods return only unicode.

Pystache’s Renderer class supports a number of attributes to control how Pystache converts byte strings to unicode on input. These include the file_encoding, string_encoding, and decode_errors attributes.

The file_encoding attribute is the encoding the renderer uses to convert to unicode any files read from the file system. Similarly, string_encoding is the encoding the renderer uses to convert any other byte strings encountered during the rendering process into unicode (e.g. context values that are encoded byte strings).

The decode_errors attribute is what the renderer passes as the errors argument to str(). The valid values for this argument are strict, ignore, and replace.

Each of these attributes can be set via the Renderer class’s constructor using a keyword argument of the same name. See the Renderer class’s docstrings for further details. In addition, the file_encoding attribute can be controlled on a per-view basis by subclassing the TemplateSpec class. When not specified explicitly, these attributes default to values set in Pystache’s defaults module.

Develop

To test from a source distribution (without installing)–

python test_pystache.py

To test Pystache with multiple versions of Python (with a single command!) and different platforms, you can use tox:

pip install tox
tox -e setup

To run tests on multiple versions with coverage, run:

tox -e py38-linux,py39-linux  # for example

(substitute your platform above, eg, macos or windows)

The source distribution tests also include doctests and tests from the Mustache spec. To include tests from the Mustache spec in your test runs:

git submodule update --init

The test harness parses the spec’s (more human-readable) yaml files if PyYAML is present. Otherwise, it parses the json files. To install PyYAML–

pip install pyyaml

Once the submodule is available, you can run the full test set with:

tox -e setup . ext/spec/specs

To run a subset of the tests, you can use nose:

pip install nose
nosetests --tests pystache/tests/test_context.py:GetValueTests.test_dictionary__key_present

Mailing List (old)

There is(was) a mailing list. Note that there is a bit of a delay between posting a message and seeing it appear in the mailing list archive.

Credits

>>> import pystache
>>> context = { 'author': 'Chris Wanstrath', 'maintainer': 'Chris Jerdonek','refurbisher': 'Steve Arnold', 'new_maintainer': 'Thomas David Baker' }
>>> print(pystache.render("Author: {{author}}\nMaintainer: {{maintainer}}\nRefurbisher: {{refurbisher}}\nNew maintainer: {{new_maintainer}}", context))
Author: Chris Wanstrath
Maintainer: Chris Jerdonek
Refurbisher: Steve Arnold
New maintainer: Thomas David Baker

Pystache logo by David Phillips is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.

0.6.0 (2021-03-04)

• Bump spec versions to latest => v1.1.3

• Modernize python and CI tools, update docs/doctests

• Update unicode conversion test for py3-only

• Add pep8speaks cfg, cleanup warnings

• Remove superfluous setup test/unused imports

• Add conda recipe/CI build

0.5.6 (2021-02-28)

• Use correct wheel name in release workflow, limit wheels

• Add install check/test of downloaded wheel

• Update/add ci workflows and tox cfg, bump to next dev0 version

0.5.5 (2020-12-16)

• fix document processing, update pandoc args and history

• add release.yml to CI, test env settings

• fix bogus commit message, update versions and tox cf

• add post-test steps for building pkgs with/without doc updates

• add CI build check, fix MANIFEST.in pruning

0.5.4-2 (2020-11-09)

• Merge pull request #1 from sarnold/rebase-up

• Bugfix: test_specloader.py: fix test_find__with_directory on other OSs

• Bugfix: pystache/loader.py: remove stray windows line-endings

• fix crufty (and insecure) http urls

• Bugfix: modernize python versions (keep py27) and fix spec_test load cmd

0.5.4 (2014-07-11)

• Bugfix: made test with filenames OS agnostic (issue #162).

0.5.3 (2012-11-03)

• Added ability to customize string coercion (e.g. to have None render as '') (issue #130).

• Added Renderer.render_name() to render a template by name (issue #122).

• Added TemplateSpec.template_path to specify an absolute path to a template (issue #41).

• Added option of raising errors on missing tags/partials: Renderer(missing_tags='strict') (issue #110).

• Added support for finding and loading templates by file name in addition to by template name (issue #127). [xgecko]

• Added a parse() function that yields a printable, pre-compiled parse tree.

• Added support for rendering pre-compiled templates.

• Added Python 3.3 to the list of supported versions.

• Added support for PyPy (issue #125).

• Added support for Travis CI (issue #124). [msabramo]

• Bugfix: defaults.DELIMITERS can now be changed at runtime (issue #135). [bennoleslie]

• Bugfix: exceptions raised from a property are no longer swallowed when getting a key from a context stack (issue #110).

• Bugfix: lambda section values can now return non-ascii, non-unicode strings (issue #118).

• Bugfix: allow test_pystache.py and tox to pass when run from a downloaded sdist (i.e. without the spec test directory).

• Convert HISTORY and README files from reST to Markdown.

• More robust handling of byte strings in Python 3.

• Added Creative Commons license for David Phillips’s logo.

0.5.2 (2012-05-03)

• Added support for dot notation and version 1.1.2 of the spec (issue #99). [rbp]

• Missing partials now render as empty string per latest version of spec (issue #115).

• Bugfix: falsey values now coerced to strings using str().

• Bugfix: lambda return values for sections no longer pushed onto context stack (issue #113).

• Bugfix: lists of lambdas for sections were not rendered (issue #114).

0.5.1 (2012-04-24)

• Added support for Python 3.1 and 3.2.

• Added tox support to test multiple Python versions.

• Added test script entry point: pystache-test.

• Added __version__ package attribute.

• Test harness now supports both YAML and JSON forms of Mustache spec.

• Test harness no longer requires nose.

0.5.0 (2012-04-03)

This version represents a major rewrite and refactoring of the code base that also adds features and fixes many bugs. All functionality and nearly all unit tests have been preserved. However, some backwards incompatible changes to the API have been made.

Below is a selection of some of the changes (not exhaustive).

Highlights:

• Pystache now passes all tests in version 1.0.3 of the Mustache spec. [pvande]

• Removed View class: it is no longer necessary to subclass from View or from any other class to create a view.

• Replaced Template with Renderer class: template rendering behavior can be modified via the Renderer constructor or by setting attributes on a Renderer instance.

• Added TemplateSpec class: template rendering can be specified on a per-view basis by subclassing from TemplateSpec.

• Introduced separation of concerns and removed circular dependencies (e.g. between Template and View classes, cf. issue #13).

• Unicode now used consistently throughout the rendering process.

• Expanded test coverage: nosetests now runs doctests and ~105 test cases from the Mustache spec (increasing the number of tests from 56 to ~315).

• Added a rudimentary benchmarking script to gauge performance while refactoring.

• Extensive documentation added (e.g. docstrings).

Other changes:

• Added a command-line interface. [vrde]

• The main rendering class now accepts a custom partial loader (e.g. a dictionary) and a custom escape function.

• Non-ascii characters in str strings are now supported while rendering.

• Added string encoding, file encoding, and errors options for decoding to unicode.

• Removed the output encoding option.

• Removed the use of markupsafe.

Bug fixes:

• Context values no longer processed as template strings. [jakearchibald]

• Whitespace surrounding sections is no longer altered, per the spec. [heliodor]

• Zeroes now render correctly when using PyPy. [alex]

• Multline comments now permitted. [fczuardi]

• Extensionless template files are now supported.

• Passing **kwargs to Template() no longer modifies the context.

• Passing **kwargs to Template() with no context no longer raises an exception.

0.4.1 (2012-03-25)

• Added support for Python 2.4. [wangtz, jvantuyl]

0.4.0 (2011-01-12)

• Add support for nested contexts (within template and view)

• Add support for inverted lists

• Decoupled template loading

0.3.1 (2010-05-07)

• Fix package

0.3.0 (2010-05-03)

• View.template_path can now hold a list of path

• Add {{& blah}} as an alias for {{{ blah }}}

• Higher Order Sections

• Inverted sections

0.2.0 (2010-02-15)

• Bugfix: Methods returning False or None are not rendered

• Bugfix: Don’t render an empty string when a tag’s value is 0. [enaeseth]

• Add support for using non-callables as View attributes. [joshthecoder]

• Allow using View instances as attributes. [joshthecoder]

• Support for Unicode and non-ASCII-encoded bytestring output. [enaeseth]

• Template file encoding awareness. [enaeseth]

0.1.1 (2009-11-13)

• Ensure we’re dealing with strings, always

• Tests can be run by executing the test file directly

0.1.0 (2009-11-12)

• First release