Add languages() to the Starlark lint API (mendixlabs/mxcli#1306)

.claude/skills/fix-issue/findings/mdl-other.jsonl

@@ -103,4 +103,5 @@
 {"area": "mdl/linter", "date": "2026-10-07", "symptom": "upstream mendixlabs/mxcli#1217: \"Lint CONV011 (NoCommitInLoop) misses CHANGE … COMMIT (and CREATE … COMMIT) inside a loop; only a separate COMMIT activity is flagged\". `change $T (\"Done\" = true) commit;` in a loop passed lint and `check`; `change …; commit $T;` was flagged. Studio Pro's recommender flags both (MXP004).", "cause": "CONV011 matched only `*microflows.CommitObjectsAction`; the Commit property of CreateObjectAction / ChangeObjectAction was never consulted. MDL-PERF01 (check-time twin, #1186) pinned its boundary to CONV011's, so it inherited the same gap by design.", "file": "`mdl/linter/rules/conv_loop_commit.go` (`committingActionKind`), `mdl/executor/validate_commit_in_loop.go` (ChangeObjectStmt/CreateObjectStmt cases); tests `conv_loop_commit_test.go`, `validate_commit_in_loop_test.go`; example `mdl-examples/bug-tests/1217-commit-clause-in-loop.mdl`", "insight": "**A rule that detects a database effect must enumerate every action that HAS the effect, not the action NAMED after it.** Commit is a property on create/change as well as an activity of its own; grep the action types for a `Commit` field before trusting a commit rule's coverage. Any value other than `No` commits — YesWithoutEvents skips handlers, not the round trip. When two rules share a pinned boundary (CONV011 ↔ MDL-PERF01), a coverage fix lands in both in the same change or they drift. Verified end to end: exec the repro into testdata/expr-checker/minimal.mpr and `lint -r CONV011` — reverted build flags 1 of 3 (only the separate commit), fixed build 3 of 3, list-commit-after-loop control quiet in both.", "refs": ["mendixlabs/mxcli#1217", "mendixlabs/mxcli#1186"], "rules": ["CONV011", "MDL-PERF01"]}
 {"area": "mdl/exprcheck", "date": "2026-10-07", "symptom": "mendixlabs/mxcli#1216: `declare $D DateTime = parseDateTimeUTC($Text, 'yyyy-MM-dd', empty);` — `mxcli check -p` reports `parseDateTimeUTC() expects 2 argument(s), got 3. [E006]` and exec refuses, while mx check on 11.14.0 reports 0 errors; only --no-check writes it", "cause": "funcTable listed the parse functions without their default-value overloads: parseDateTime/parseDateTimeUTC(value, format [, default]), parseInteger(value [, default]), parseDecimal(value [, format [, default]]) were all fixed at their minimum arity", "file": "`mdl/exprcheck/func_checker.go` (funcTable), test `mdl/exprcheck/parse_default_arity_test.go`, `mdl-examples/bug-tests/1216-parse-datetime-default-value.mdl`", "insight": "funcTable arities are a transcription, so widen each one only by measurement, and measure the siblings the reporter says 'presumably' — two of them (parseInteger/parseDecimal) had the same false E006, but parseBoolean($s, false) is CE0117 and stays 1-arg. Isolate each case in its own project copy: mx check names the activity by its caption ('Create Date and time variable'), so several cases in one project are indistinguishable. Plausible wrong turn: a default of currentDateTime() fails CE0117, which reads as 'the 3-arg UTC form is invalid' — it is currentDateTime() itself, rejected on its own in a microflow; vary the default ($var, empty) before concluding. E006 only fires with -p, so a project-less `mxcli check` of the repro passes and proves nothing.", "ce": ["CE0117"], "rules": ["E006"]}
 {"area": "mdl/exprcheck", "date": "2026-10-07", "symptom": "`declare $D DateTime = currentDateTime();` passes `mxcli check` and `exec`, then mx check on 11.14.0 fails `[error] [CE0117] \"Error(s) in expression.\" at Create variable activity 'Create Date and time variable'` — in a microflow and a nanoflow alike", "cause": "funcTable listed `currentDateTime` as a zero-argument built-in. Mendix has no such function; the current time is the `[%CurrentDateTime%]` token. funcTable is MDL044's sole allow-list, so the entry silenced the one rule that would have caught it", "file": "`mdl/exprcheck/func_checker.go` (entry removed), `mdl/exprcheck/unknown_funcs.go` (tokenFuncs → FuncRef.Token), `mdl/executor/validate_microflow.go` (MDL044 hint), bug tests `current-datetime-function.fail.mdl` / `current-datetime-token.mdl`", "insight": "Found by accident while measuring #1216: a default of currentDateTime() made parseDateTime look like it rejected a third argument. Before blaming the outer construct, build the inner expression on its own. The removal alone would give a useless hint — nearestFunc offers a spelling match, and the right answer is a token rather than a function — so name the token in the hint. Nothing in the repo emitted or recommended currentDateTime() (every example uses the token), which suggests the entry came from transcription, like the year()/month()/trunc() entries before it. The remaining unverified extraction names (dayOfYear, hour, …) are the same risk.", "ce": ["CE0117"], "rules": ["MDL044"]}
+{"area": "mdl/linter", "date": "2026-10-07", "symptom": "A Starlark lint rule cannot tell which project languages are enabled: strings() returns rows for every stored translation (a fresh en_US-only 11.12.5 app already has 124 nl_NL rows), enabling nl_NL changes nothing a rule sees, and a rule calling languages() is skipped with 'undefined: languages (a builtin this mxcli does not have — the rule may need a newer mxcli)'", "cause": "No builtin exposed Settings$LanguageSettings.Languages; LintReader had no GetProjectSettings, so the only language data a rule could reach was the catalog's strings table, which indexes stored translations, not enabled languages", "fix": "languages() builtin returning struct language{code,is_default,check_completeness} from LintReader.GetProjectSettings (added to the interface; the backend already implements it). Classified CatalogFast; a reader error fails the rule instead of answering []", "insight": "Stored translations are not the enabled set: Studio Pro and the starter app keep texts in languages the project never enabled, so any 'per language' check built on strings() over-reports. Project-level facts belong on the reader path (like project_security()), not in the catalog, so they need no FULL build. A new builtin trips three guards at once — builtinModes, the skill's builtin list and its struct table — which is the checklist", "issue": "mendixlabs/mxcli#1306", "file": "mdl/linter/starlark.go (builtinLanguages); mdl/linter/context.go (LintReader)", "test": "mdl/linter/starlark_languages_test.go"}
 {"area": "mdl/catalog", "date": "2026-10-07", "symptom": "activities_for() / CATALOG.ACTIVITIES returns every call and delete with its target empty: `MicroflowCallAction: action_ref=\"\" entity_ref=\"\" service_ref=\"\"` (also NanoflowCallAction, JavaActionCallAction, JavaScriptActionCallAction, DeleteObjectAction); no column says which call runs in a task queue; a nanoflow's JavaScript action call has no refs_from() row. refs_from() names the call/delete targets fine, and the lint run reports nothing.", "cause": "describeAction (builder_microflows.go) filled ActionRef/EntityRef only for REST/web service/OData calls and create/retrieve; the call and delete cases were never written. The delete's entity was resolvable all along via buildVarEntityMap, which only the refs builder used. microflowActionRef had no JavaScriptActionCallAction case.", "file": "`mdl/catalog/builder_microflows.go` (describeAction, insertFlowActivities), `mdl/catalog/builder_references.go` (microflowActionRef), `mdl/catalog/tables.go` (QueueRef, schema 23)", "insight": "Two builders derive per-action facts from the same parsed actions -- the refs switch and the activities switch -- and drift independently: an action can have its target in refs and an empty column in activities. When a row field is empty, check whether the other switch already resolves it before writing new resolution; here the delete's entity reused buildVarEntityMap (params, create/retrieve outputs, loop iterators) per flow. The queue lives on MicroflowCall.QueueSettings.Queue (and JavaActionCallAction.QueueSettings), not a top-level Queue. A new activities column breaks hand-built `CREATE TABLE activities` fixtures in linter tests (COALESCE does not cover a missing column) and needs a CatalogSchemaVersion bump. Control: HEAD binary on the issue's repro prints exactly the reported empty rows.", "refs": ["mendixlabs/mxcli#1305", "mendixlabs/mxcli#1266", "mendixlabs/mxcli#1267"]}

.claude/skills/mendix/write-lint-rules/SKILL.md

@@ -80,6 +80,7 @@ Without this, a rule that reads a full-only table under a fast build gets
 | `module_roles()` | list of module_role | All module roles (deduplicated from role mappings) |
 | `role_mappings()` | list of role_mapping | User role to module role assignments |
 | `project_security()` | project_security or None | Project-level security settings (requires MPR reader) |
+| `languages()` | list of language | The languages **enabled** in the project settings, in settings order (requires MPR reader; `[]` without one). Use it to scope per-language checks: `strings()` has a row for every stored translation, including languages the project never enabled |
 | `xpath_expressions()` | list of xpath_expression | All XPath constraint expressions in the catalog (access rules, retrieve actions, widgets) (full catalog — auto-detected) |
 | `modules()` | list of module | The user's modules (not System, not Marketplace), with their domain model's documentation |
 | `associations()` | list of association | All non-system associations, same-module and cross-module, with the delete behaviour of both ends |
@@ -572,6 +573,16 @@ Returned by `project_security()`. Returns `none` if no MPR reader is available.
 | `require_mixed_case` | bool | Must contain upper and lower case |
 | `require_symbol` | bool | Must contain a symbol |
 
+### language
+
+Returned by `languages()`, one per language enabled in the project settings. A per-language check skips `strings()` rows whose `language` is not among these codes.
+
+| Property | Type | Description |
+|----------|------|-------------|
+| `code` | string | Language code: `"en_US"`, `"nl_NL"` |
+| `is_default` | bool | Whether this is the project's default language |
+| `check_completeness` | bool | Whether Studio Pro checks this language's translations for completeness |
+
 ## Helper Functions
 
 | Function | Description |

CHANGELOG.md

@@ -8,6 +8,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
 
 ### Added
 
+- **`languages()` in Starlark lint rules — the languages enabled in the project** (mendixlabs/mxcli#1306) — a rule had no way to tell which languages are enabled: `strings()` has a row for every stored translation, and a fresh en_US-only app already carries nl_NL texts, so enabling a language changed nothing a rule could see, and `languages()` failed to load with `undefined: languages`. It returns one `language` per enabled language, from the project settings, with `code`, `is_default` and `check_completeness`, so a per-language check (every page title translated into each enabled language) can filter `strings()` to the enabled codes. It reads the project settings, not the catalog, so it needs no full catalog build; a failed settings read fails the rule instead of answering `[]`.
 - **A published REST service's authentication** (mendixlabs/mxcli#1331) — `create [or modify] published rest service M.Api (…, Authentication: (basic, session, microflow M.Authenticate))` sets Studio Pro's **Requires authentication** and its methods: `basic` (username and password), `session` (active session), `microflow M.F` (custom); `Authentication: none` is "Requires authentication: No". The methods are stored in the order written, which is how Studio Pro stores the ones ticked, and `describe` prints them in the stored order (it omits `none`). Left out, `create or modify` and `alter` keep the stored setting, as before. `alter published rest service M.Api set ( Key: value, … )` now takes create's property list (`Path`, `Version`, `ServiceName`, `Authentication`); `set Key = '…'` still works. The authentication microflow must return `System.User` and take only a `System.HttpRequest` and/or `System.HttpResponse` (Mendix: CE0334, CE0336, measured with `mx check` on 11.14.0); `exec` and `check --references` refuse anything else as **MDL-REST04**. Executing the `describe` output of each of ako/TestApp's Studio Pro services writes nothing.
 - **`send email` — the built-in Send Email activity (Mendix 11.13+, beta)** — `send email ( From: …, To: …, Subject: 'Order {1}' with ({1} = …), Body: template '…', HtmlBody: template '…', Headers: ('X-Name': 'value'), Attachment: $Doc, Host: …, Port: …, SecurityType: ssl, CheckServerIdentity: true, ConnectionTimeout: 30000, Authentication: basic (Username: …, Password: …) ) [on error …];` creates a `Microflows$SendEmailAction`, which sends SMTP mail without the Email Connector module. The settings are one property list (ADR-0013), keyed by the metamodel's names; an unknown, repeated or misshapen key is an error, and so is a missing From, Host, Port or recipient (mxbuild: CE0166). `describe microflow` renders the activity instead of `-- Unsupported action: Microflows$SendEmailAction`, and the description re-executes to the same activity. `check` type-checks its expressions (E009: String addresses, host and credentials, Integer/Long port, String template parameters — what mxbuild reports as CE9528/CE0117), and warns on a server-identity check without SSL and on header names Studio Pro would refuse (MDL-EMAIL02/03). A 10.x–11.12 project is refused; a stored activity MDL cannot restate (authentication document, pre-11.13 message) still describes as unsupported rather than being rewritten smaller. `mxcli syntax microflow.send-email`. (mendixlabs/mxcli#1315)
 - **`mxcli playwright check` — a text verdict for pages of a running app, in one call** — `mxcli playwright check /p/a /p/b -p app.mpr` loads each page in one headless browser and prints the verdict `run --page-check` prints (title, heading, rows, visible text, error banners, console errors) plus failed same-origin requests and the HTTP status, then `OK n page(s)` or `FAIL k of n page(s)`. **Exit status** 0 all passed, 1 a page failed (HTTP error, sign-in form or a 401 instead of the page, an error banner or error dialog, a console error, a failed request, a failed assertion), 2 the check could not run. It signs in when needed — `--user/--password`, `--role R` (the project's demo user with that user role), or with only `-p` a demo user — saves the session under `.mxcli/playwright-check/`, reuses it on the next check and renews it when the runtime has restarted. `--assert-text`, `--assert-count 'SELECTOR>=N'`, and `--screenshot out.png`, which prints the path and never the image. It replaces the hand-written playwright-cli login/goto/sleep/eval/screenshot sequences that were about a sixth of the tool calls in a measured app-building session, each ending in a PNG read; the `test-app` and `verify-in-runtime` skills and `/mendix:test` now route "check a page" to it.

mdl-examples/bug-tests/1306-lint-languages-builtin.mdl

@@ -0,0 +1,21 @@
+mdl 1;
+-- ============================================================================
+-- mendixlabs/mxcli#1306 — a Starlark lint rule could not read the enabled
+-- project languages
+-- ============================================================================
+--
+-- Reported: strings() returns rows for every stored translation, including
+-- languages that are not enabled (a fresh en_US-only app already carries nl_NL
+-- texts), so enabling nl_NL changed nothing a rule could see; a rule calling
+-- languages() was skipped with "undefined: languages".
+--
+-- The assertion is a Go test (mdl/linter/starlark_languages_test.go): the
+-- symptom is in the lint API, which `make check-mdl` does not exercise. This
+-- script is the model change from the report. To reproduce by hand on a fresh
+-- `mxcli new` app, run it, then lint a rule that returns
+--   [violation(message = l.code) for l in languages()]
+-- before it, languages() lists en_US only; after it, en_US and nl_NL, while
+-- strings() reports the same per-language counts both times.
+-- ============================================================================
+
+alter settings LANGUAGE add or modify 'nl_NL' (CheckCompleteness: true);

mdl/linter/context.go

@@ -24,6 +24,7 @@ type LintReader interface {
 	GetMicroflow(id model.ID) (*microflows.Microflow, error)
 	ListMicroflows() ([]*microflows.Microflow, error)
 	GetProjectSecurity() (*security.ProjectSecurity, error)
+	GetProjectSettings() (*model.ProjectSettings, error)
 	GetNavigation() (*types.NavigationDocument, error)
 	ListPages() ([]*pages.Page, error)
 	ListModules() ([]*model.Module, error)

mdl/linter/rules/dataview_layout_grid_test.go

@@ -134,11 +134,12 @@ func (r rawUnitReader) ListMicroflows() ([]*microflows.Microflow, error)     { r
 func (r rawUnitReader) GetProjectSecurity() (*security.ProjectSecurity, error) {
 	return nil, nil
 }
-func (r rawUnitReader) GetNavigation() (*types.NavigationDocument, error) { return nil, nil }
-func (r rawUnitReader) ListPages() ([]*pages.Page, error)                 { return nil, nil }
-func (r rawUnitReader) ListModules() ([]*model.Module, error)             { return nil, nil }
-func (r rawUnitReader) ListFolders() ([]*types.FolderInfo, error)         { return nil, nil }
-func (r rawUnitReader) GetRawUnit(id model.ID) (map[string]any, error)    { return r.units[id], nil }
+func (r rawUnitReader) GetProjectSettings() (*model.ProjectSettings, error) { return nil, nil }
+func (r rawUnitReader) GetNavigation() (*types.NavigationDocument, error)   { return nil, nil }
+func (r rawUnitReader) ListPages() ([]*pages.Page, error)                   { return nil, nil }
+func (r rawUnitReader) ListModules() ([]*model.Module, error)               { return nil, nil }
+func (r rawUnitReader) ListFolders() ([]*types.FolderInfo, error)           { return nil, nil }
+func (r rawUnitReader) GetRawUnit(id model.ID) (map[string]any, error)      { return r.units[id], nil }
 func (r rawUnitReader) ListScheduledEvents() ([]*model.ScheduledEvent, error) {
 	return nil, nil
 }

mdl/linter/starlark.go

@@ -417,6 +417,7 @@ func (r *StarlarkRule) buildPredeclared() starlark.StringDict {
 		"module_roles":     starlark.NewBuiltin("module_roles", r.builtinModuleRoles),
 		"role_mappings":    starlark.NewBuiltin("role_mappings", r.builtinRoleMappings),
 		"project_security": starlark.NewBuiltin("project_security", r.builtinProjectSecurity),
+		"languages":        starlark.NewBuiltin("languages", r.builtinLanguages),
 
 		// XPath / expression analysis
 		"xpath_expressions": starlark.NewBuiltin("xpath_expressions", r.builtinXPathExpressions),
@@ -914,6 +915,39 @@ func (r *StarlarkRule) builtinProjectSecurity(_ *starlark.Thread, _ *starlark.Bu
 	}), nil
 }
 
+// builtinLanguages returns the languages enabled in the project settings
+// (mendixlabs/mxcli#1306). strings() cannot answer this: it has a row for every
+// stored translation, and a project carries texts in languages it never
+// enabled. A failed settings read fails the rule rather than answering [],
+// which a per-language rule would report as clean.
+func (r *StarlarkRule) builtinLanguages(_ *starlark.Thread, b *starlark.Builtin, args starlark.Tuple, kwargs []starlark.Tuple) (starlark.Value, error) {
+	if err := starlark.UnpackArgs(b.Name(), args, kwargs); err != nil {
+		return nil, err
+	}
+	if r.ctx == nil || r.ctx.Reader() == nil {
+		return starlark.NewList(nil), nil
+	}
+	ps, err := r.ctx.Reader().GetProjectSettings()
+	if err != nil {
+		return nil, fmt.Errorf("%s: reading project settings: %w", b.Name(), err)
+	}
+	if ps == nil || ps.Language == nil {
+		return starlark.NewList(nil), nil
+	}
+	var out []starlark.Value
+	for _, l := range ps.Language.Languages {
+		if l.Code == "" {
+			continue
+		}
+		out = append(out, starlarkstruct.FromStringDict(starlark.String("language"), starlark.StringDict{
+			"code":               starlark.String(l.Code),
+			"is_default":         starlark.Bool(l.Code == ps.Language.DefaultLanguageCode),
+			"check_completeness": starlark.Bool(l.CheckCompleteness),
+		}))
+	}
+	return starlark.NewList(out), nil
+}
+
 // entityToStarlark converts an Entity to a Starlark struct.
 func entityToStarlark(e Entity) starlark.Value {
 	return starlarkstruct.FromStringDict(starlark.String("entity"), starlark.StringDict{