Normalize rendered template output for pre-commit#548
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Bakery's Jinja-rendered files (Containerfiles, goss.yaml, scripts, and bakery.yaml itself) could ship with trailing whitespace or a missing trailing newline, failing the trailing-whitespace and end-of-file-fixer pre-commit hooks in consuming repos. Release PRs in images-connect (#77, #87) failed CI for exactly this reason. Add normalize_rendered_output() that strips trailing spaces and tabs from each line and ensures a single trailing newline, matching the output of those two pre-commit hooks. Apply it at every site that writes a rendered template: - ImageVersion.render_files (Containerfile and other templates) - ImageMatrix.render_files (Containerfile and other templates) - BakeryConfig.new (initial bakery.yaml) - BakeryConfig.write (updates to bakery.yaml, replacing the inline re.sub strip added in 48dea80) - BakeryConfigDocument when scaffolding a new Containerfile template Also drop the dead render_kwargs["trim_blocks"] = True branch from ImageVersion and ImageMatrix. trim_blocks is a Jinja2 Environment option, not a Template.render() argument, so passing it through .render() was a silent no-op that just added it to the template context. Removing it doesn't change rendered output because it never took effect; the new normalize step covers the same intent more robustly.
ianpittwood
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May 27, 2026
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LGTM, thanks for fixing this!
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Bakery's Jinja-rendered files (Containerfiles, goss.yaml, scripts, and bakery.yaml itself) could ship with trailing whitespace or a missing trailing newline, failing
trailing-whitespaceandend-of-file-fixerpre-commit hooks in consuming repos. Two release PRs failed CI for exactly this reason:The root cause was two compounding bugs in the renderer. First,
ImageVersion.render_filesandImageMatrix.render_filestried to enabletrim_blocksfor Containerfile templates by passing it totpl.render(trim_blocks=True)— buttrim_blocksis a Jinja2Environmentoption, not aTemplate.render()argument, so it was a silent no-op that just landed in the template context. Second, no rendered-template write path normalized whitespace exceptBakeryConfig.write(), which had a one-offre.subadded after the first failure. Everything else (Containerfiles viaversion.py/matrix.py, goss.yaml, scripts, scaffoldedbakery.yaml) wrote raw Jinja output, so{% for %} ... {% endfor %}blocks left lines containing only their leading indent — exactly what PR #87 caught inconnect/2026.04/test/goss.yaml.normalize_rendered_output()inposit_bakery/config/templating/render.pystrips trailing spaces and tabs from each line and ensures a single trailing newline, matching what the two pre-commit hooks produce. It's now applied at every rendered-file write site, andBakeryConfig.write()'s inlinere.subis replaced by it for consistency. The deadrender_kwargs["trim_blocks"] = Truebranch is removed since it never took effect; the new normalize step covers the same intent more robustly.Verified by re-rendering all images in
images-connect,images-package-manager, andimages-workbenchagainst the patched bakery — full pre-commit suite passes on all three.