feat(config): Add Tera template support to miserc.toml#8867
Merged
Conversation
Contributor
There was a problem hiding this comment.
Code Review
This pull request introduces Tera template support for .miserc.toml configuration files, allowing for dynamic settings based on environment variables, XDG paths, and OS-level context. The implementation includes a lazy-loaded Tera instance with a restricted context to prevent circular dependencies during early initialization. Documentation and tests have been updated to reflect these changes. Feedback suggests adding a warning log if the current working directory cannot be retrieved during template rendering to improve debuggability.
Contributor
Greptile SummaryThis PR introduces Tera template support for The implementation is clean and well-considered: Tera is lazily initialized only when template markers ( Key changes:
Confidence Score: 5/5Safe to merge; all prior P1 concerns are resolved and only a P2 test coverage gap remains All three previously flagged issues (misleading get_miserc_tera doc comment, TERA_ACCESSED_FILES pollution, test using wrong env source) have been correctly addressed. The remaining finding is a P2 test quality issue — the e2e tests don't assert that rendering actually happened, but the feature itself is functionally correct and well-guarded by the unit tests in miserc.rs. No logic, data-integrity, or security issues found. e2e/config/test_miserc — the two new template test scenarios do not strongly verify that Tera rendering occurred; a false regression in render_miserc_template could go undetected Important Files Changed
Sequence DiagramsequenceDiagram
participant main as mise init
participant miserc as miserc::init()
participant load as load_miserc_settings()
participant render as render_miserc_template()
participant tera as Tera (TERA static)
participant toml as TOML parser
main->>miserc: init()
miserc->>load: load_miserc_settings()
load->>load: find_miserc_files()
loop for each miserc file (reversed precedence)
load->>render: &mut tera, content, config_root
alt content contains {{ or {% or {#
render->>tera: get_or_insert_with(get_miserc_tera)
tera-->>render: TERA.clone()
render->>render: build Context (env/config_root/cwd/xdg_*)
render->>tera: render_str(content, context)
alt render OK
tera-->>render: rendered string
else render Err
tera-->>render: error
render->>render: warn! + return raw content
end
else no template syntax detected
render-->>render: return content unchanged (fast path)
end
render-->>load: final content string
load->>toml: from_str::<MisercSettings>(&content)
toml-->>load: Ok(settings) or warn on Err
load->>load: merge_settings()
end
load-->>miserc: MisercSettings
miserc->>miserc: MISERC.set(settings)
miserc->>miserc: take_tera_accessed_files() — discard file-tracking artifacts
miserc-->>main: Ok(())
Reviews (11): Last reviewed commit: "test(config): fix e2e dummy version asse..." | Re-trigger Greptile |
Render Tera templates in .miserc.toml before TOML parsing, enabling
expressions like `ceiling_paths = ["{{ env.HOME }}"]`. Uses a minimal
context (env, cwd, config_root, xdg_*, arch/os functions) safe for
early initialization — before Settings or main config are loaded.
Unavailable: mise_env (circular), exec()/read_file() (need Settings).
Falls back to raw content with a warning on render failure.
https://claude.ai/code/session_01525Mu3hgS2M2rKtDUv6CpT
- Remove useless format!() macro in test (clippy::useless_format) - Fix duplicate ceiling_paths key in docs example (invalid TOML) - Replace misleading e2e test that used uname instead of os() template https://claude.ai/code/session_01525Mu3hgS2M2rKtDUv6CpT
- Avoid redundant TERA clones: create Tera instance once before the
file loop instead of once per file (render_str requires &mut Tera)
- Fix incorrect docs claim that read_file() requires Settings — it
does not; it is excluded to keep early-init context minimal
- Document {% raw %} escape for users with literal {{ in miserc values
https://claude.ai/code/session_01525Mu3hgS2M2rKtDUv6CpT
The previous refactor unintentionally cloned TERA unconditionally on every startup, even when no miserc files exist or none contain template syntax. Switch to Option<Tera> so the clone only occurs when a file with template syntax is actually encountered. Also fix the inline docstring which still incorrectly stated that read_file() depends on Settings (it does not). https://claude.ai/code/session_01525Mu3hgS2M2rKtDUv6CpT
The docstring incorrectly stated read_file depends on Settings. Only exec() depends on Settings; read_file() is excluded because it needs per-file directory context not available at this stage. https://claude.ai/code/session_01525Mu3hgS2M2rKtDUv6CpT
- Clear TERA_ACCESSED_FILES after miserc loading so hash_file/file_size/ last_modified filters don't silently pollute hook-env's file-watch list - Fix get_miserc_tera() docstring: exec/read_file are absent because they are only registered in get_tera(), not in the TERA static itself - Fix test_render_miserc_template_env_var to read HOME from PRISTINE_ENV (same source as the template context) rather than std::env::var - Log current_dir() failures at debug level so the missing `cwd` context is diagnosable with MISE_DEBUG=1 https://claude.ai/code/session_01525Mu3hgS2M2rKtDUv6CpT
563fd7c to
62fedc2
Compare
- Also clear TERA_ACCESSED_FILES in miserc::get() fallback path, not
just miserc::init(), so the cleanup is consistent regardless of which
path triggers loading
- Break long debug!() line for rustfmt compliance
- Wrap miserc template examples in <div v-pre> to prevent VitePress/Vue
from interpreting {{ }} as interpolation (fixes docs build CI failure)
https://claude.ai/code/session_01525Mu3hgS2M2rKtDUv6CpT
- Wrap {{ }} and {% %} in <div v-pre> and <span v-pre> to prevent
VitePress/Vue from treating them as interpolation (fixes CI build)
- Add explicit {#miserc-template-support} anchor to heading with dots
to avoid ambiguous GFM anchor generation (fixes MD051)
- Rename duplicate '### Examples' heading to '### miserc.toml Examples'
(fixes MD024)
- Update cross-references to use the explicit anchor ID
https://claude.ai/code/session_01525Mu3hgS2M2rKtDUv6CpT
dummy '1' resolves to 1.1.0 in the e2e environment (established by the existing MISE_ENV=ci test at line 14). Our new template tests incorrectly asserted 1.0.0. https://claude.ai/code/session_01525Mu3hgS2M2rKtDUv6CpT
mise-en-dev
added a commit
that referenced
this pull request
Apr 7, 2026
### 🚀 Features - **(config)** Add Tera template support to miserc.toml by @richardthe3rd in [#8867](#8867) ### 🐛 Bug Fixes - **(env)** include tools-only redactions in `mise env --redacted` by @jakedgy in [#8956](#8956) - **(env)** pass dependency env to vfox backend plugin hooks by @cprecioso in [#8952](#8952) - **(shim)** fix race condition when removing in make_shim, when multiple plugins provide the same shim by @brander-john in [#8947](#8947) - **(spm)** derive API URL from host for self-hosted instances by @ThomasDutartre in [#8955](#8955) - **(task)** resolve env vars in usage tera templates when flags are provided by @jdx in [#8957](#8957) ### 📚 Documentation - **(python)** clarify attestation settings must be under [settings] in mise.toml by @fru1tworld in [#8939](#8939) ### 📦 Registry - added sing-box by @tony-sol in [#8944](#8944) ### Chore - **(ci)** remove auto-draft PR workflow by @jdx in [#8945](#8945) ### New Contributors - @ThomasDutartre made their first contribution in [#8955](#8955) - @jakedgy made their first contribution in [#8956](#8956) - @brander-john made their first contribution in [#8947](#8947) - @fru1tworld made their first contribution in [#8939](#8939)
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
This pull request adds support for Tera templating in
.miserc.tomlfiles, allowing users to use environment variables and other OS-level context in their configuration. The implementation ensures templates are rendered safely during early initialization, and provides documentation, tests, and end-to-end validation for this feature.Template support in
.miserc.toml:.miserc.tomlfiles, enabling use of environment variables and other OS-level context in configuration values. The context includesenv,config_root,cwd, XDG directories, and basic functions/filters, but excludes settings-dependent or self-referential values. [1] [2] [3]docs/configuration/environments.mdanddocs/templates.mdto describe template support, available context, usage examples, and caveats for.miserc.toml. [1] [2] [3]Testing and validation:
.miserc.toml, covering environment variable expansion, function calls, context injection, and fallback behavior on errors..miserc.tomlscenarios.Internal changes:
get_miserc_tera, ensuring correct function/filter registration for early config parsing.