bcquality/microsoft/skills/review/al-style-review.md
Michael Dieringer 0a8c9a8556
18 AL/BC patterns: style, data-modeling, web-services, appsource, breaking-changes, performance, testing (#156)
* Add 18 community AL/BC patterns across style, data-modeling, web-services, appsource, breaking-changes, performance, and testing

Contributed by CURABIS ApS, generalized from patterns observed across real AppSource/PTE development. Each article follows the knowledge file format (frontmatter, Description/Best Practice/Anti Pattern, sibling .good.al/.bad.al samples).

* Address Jesper Schulz-Wedde's review on PR #156

- Rename 3 articles so their .good.al/.bad.al companion stems match
  (do-not-change-primary-key, testfield-required-setup-field,
  al-identifiers-english), fixing the R14 orphan-sample errors.
- do-not-change-primary-key.good.al: include Flow in the new table's
  own primary key so it actually models the discriminating dimension.
- al-build-output-must-not-pollute-project-root.md: drop the
  unsubstantiated AL0197 causal claim and the non-existent
  al.outputPath setting; reframe as build-artifact hygiene sourced
  from ALTool --outfolder / al_build outputPath.
- prefer-email-module.md: Email Message is Codeunit 8904, not a table;
  distinguish it from the underlying Sent/Outbox/Draft storage.
- file-datatype-saas.md: File.Open/Create/Read/Write fails to compile
  against a Cloud-scoped project, it does not compile and silently
  fail at runtime.
- namespace-must-be-verified-from-source.md: narrow to "resolve from
  the referenced object's source or symbols," since source-file line
  one is not the only authoritative source (symbol packages, comments
  before the namespace line).
- test-data-must-be-random-and-complete.md: drop "assume an empty
  database" and "collision-free" absolutes; reframe around
  independence from unrelated business records and reserving explicit
  values for scenario-defining inputs.
- binary-choice-must-be-boolean.md: scope to genuine true/false
  semantics, not mechanical two-member-enum-to-boolean conversion.
- document-report-word-layout.md: scope down to a sourced Microsoft
  Learn recommendation instead of an unconditional performance
  guarantee; cite the three Learn pages.
- Wire the new articles into their review skills' candidate-selection
  signals (file-datatype-saas, prefer-email-module,
  namespace-must-be-verified-from-source, var-parameters-require-an-
  addressable-variable) so they can actually enter a worklist.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

* Fix dimension-management-wiring.md: ValidateShortcutDimCode and CreateDim
do not exist on the current DimensionManagement codeunit

Verified against microsoft/BCApps: the real master-table validation
procedure is ValidateDimValueCode (or ValidateShortcutDimValues when a
DimSetID is also needed), and the real document-side inheritance
procedure is GetDefaultDimID, not CreateDim. Caught from Jesper
Schulz-Wedde's review thread, which had been partially hidden by
GitHub's comment folding.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

* Address second round of Jesper Schulz-Wedde's review on PR #156

- dimension-management-wiring.md/.good.al: split into the two distinct
  models the article was conflating - master data (Default Dimension
  records via ValidateDimValueCode/SaveDefaultDim) vs. transactional/
  document data (a single Dimension Set ID assembled via AddDimSource +
  GetDefaultDimID, verified against BCApps' ExchRateAdjmtProcess.Codeunit.al).
  Added a compiling document-table example alongside the existing master
  table one.
- Deleted api-page-flowfields-must-be-calcfields (.md/.good.al/.bad.al):
  Microsoft's own FlowFields documentation states a FlowField used as a
  control's direct source expression is automatically calculated on any
  page - no API-page exception is documented, and none could be
  reproduced.
- prefer-email-module.bad.al/.md: Codeunit Mail has no Send/GetErrorDesc
  members; fixed to the real current 7-argument CreateMessage signature,
  and corrected the claim that the legacy path "still runs" - its base
  implementation no longer sends anything, only raises integration events.
- check-post-line-batch-pattern.md/.good.al: reframed from a universal
  invariant to the standard shape, naming the real Gen./Item/CA/Res./Job/
  Insurance/Mfg. Item/FA Jnl.-Check Line/-Post Line/-Post Batch codeunits
  it's based on. Added the missing Check Line companion codeunit so the
  good fixture is internally complete.
- test-data-must-be-random-and-complete.good.al: removed leftover
  "collision-free" wording contradicting the already-corrected article text.
- fixed-choice-set-must-use-enum-not-integer.md: removed the reintroduced
  state-count heuristic ("the line is the state count"), aligned with
  binary-choice-must-be-boolean.md's semantics-based distinction.
- namespace-must-be-verified-from-source.md: removed the false claim that
  the compiler and AL Language Server use different namespace-resolution
  rules.
- intrinsic-al-functions-must-use-modern-casing.md: removed the unverified
  claim that PascalCase is the VS Code formatter's default output.

Worklist completeness: added cues for the 8 rules in data-modeling,
testing, performance, and web-services that had none (Jesper's explicit
ask), plus the same gap in all 7 style rules from this PR (not explicitly
named this round, but the identical systemic issue) - 15 cues total across
al-data-modeling-review.md, al-testing-review.md, al-performance-review.md,
al-web-services-review.md, and al-style-review.md.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

* Fix remaining correctness issues from Jesper's 2026-09-15 re-review

- dimension-management-wiring: SaveDefaultDim's third argument is the
  shortcut dimension number (1-8), not the field's AL field ID; the
  fixture passed FieldNo(...) = 10. GetDefaultDimID's InheritFromDimSetID
  must be 0 when recomputing after the linking record changes, not the
  document's existing Dimension Set ID (which would retain the previous
  customer's leftover dimensions). Verified against
  DimensionManagement.Codeunit.al and BankDepositHeader.Table.al in the
  BCApps reference clone.
- check-post-line-batch-pattern: "Post Line writes exactly one line to
  the ledger" overclaimed - Gen. Jnl.-Post Line alone calls InsertGLEntry
  from a dozen call sites (balancing entry, VAT, currency rounding,
  deferrals) and can write several G/L Entries per journal line.
  Reworded to "posts exactly one journal line" and softened the
  "distinct, non-overlapping responsibilities" absolute.
- namespace-must-be-verified-from-source.bad.al: dropped the "resolves
  in a local build, fails in VS Code" comment (taught an inherent
  compiler/language-server disagreement that isn't real); reframed as
  stale/cached symbols, matching the prose fix already made.
- file-datatype-saas.good.al: replaced the deprecated 5-argument
  UploadIntoStream overload with the current 2-argument one, and
  actually staged through TempBlob as the article's own Best Practice
  instructs (the declared TempBlob variable was previously unused).
- test-data-must-be-random-and-complete: no longer treats a
  short-but-valid value as defective merely for being "underfilled" -
  AL field lengths are maxima, not minimums. Scoped to missing values
  or a scenario with an explicit length/format requirement (e.g. a
  truncation test). Updated the al-testing-review.md routing cue to
  match.
- stored-derived-fields-must-not-be-exposed-directly: stopped mandating
  source-field exposure as part of the core pattern: the good fixture
  exposed only one of the derived value's two inputs (Hours Used, not
  Budgeted Hours), making the claimed "so the consumer can verify it"
  impossible. Reframed as an optional, all-or-nothing addition and
  fixed the fixture to expose both inputs.

Rebased onto upstream/main to resolve conflicts in
al-breaking-changes-review.md, al-data-modeling-review.md,
al-performance-review.md, and al-style-review.md against merged PRs
#148 and #153; all sides' worklist tokens/cues retained.

* Fix remaining READ-convention sample links across this PR's 18 articles

The same plain-backtick "See sample: \`x.good.al\`." form fixed on
al-methods-limited-during-write-transactions (PR #161) turned up
repo-wide on 15 more of this PR's articles - Knowledge-Retrieval.ps1
requires the markdown-link form to associate a sample with its
article. All 16 fixed; the four local validators (frontmatter,
knowledge-index, knowledge-retrieval, review-fixtures, skill-index)
pass.

* Fix two merge-critical correctness issues from Jesper's 2026-09-22 review

- api-page-key-fields-must-be-editable-on-insert.good.al and
  stored-derived-fields-must-not-be-exposed-directly.good.al: both were
  writable API pages missing DelayedInsert = true, contradicting this
  repo's own api-page-delayedinsert-true rule - the canonical "good"
  samples were teaching code BCQuality itself flags.
- dimension-management-wiring.good.al: UpdateDimensionSetID exited
  early when Customer.Get failed, leaving the previous customer's
  shortcut dimension and Dimension Set ID in place - the same staleness
  bug the InheritFromDimSetID = 0 fix (from the prior review round) was
  meant to prevent, just triggered by a failed lookup instead of a
  successful one. Now clears the shortcut field and recomputes with an
  empty source list on a failed lookup too, so GetDefaultDimID
  correctly returns an empty Dimension Set ID instead of never running.

---------

Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>
2026-09-29 12:48:17 +02:00

13 KiB

kind id version title description inputs outputs bc-version technologies countries application-area
action-skill al-style-review 1 AL style review Reviews AL source changes against naming, labelling, localization, and code-convention guidance from BCQuality.
pr-diff
file-path
folder-path
findings-report
all
al
w1
all

AL style review

Reviews AL source changes against the style knowledge domain in BCQuality and emits a findings report. This is a leaf action skill: it invokes no sub-skills. It is one of the skills composed by al-code-review.

Style findings cover AL conventions that require contextual judgment — API page naming, temporary-variable prefixes, label semantics, date-formula localization, named invocations, FieldCaption/TableCaption in user messages, error-parameter handling, and file naming. Mechanical compiler and analyzer rules are intentionally outside this skill; run the consuming app's configured analyzers separately.

An orchestrator invokes this skill with a pr-diff, file-path, or folder-path. The skill produces a single JSON document conforming to the DO output contract.

Source

Use READ's Bounded retrieval for review skills workflow with -Domain style. Consume every catalog page across enabled layers before applying this leaf's Relevance and Worklist; preserve each exact catalog path and open complete bodies only for exact paths selected by the Worklist. If the helper or prepared index is unavailable or invalid, use READ's explicit path-discovery and bounded native-read fallback.

Relevance

Apply the frontmatter matching rules defined in READ against the task context:

  • bc-version — the target BC version from the PR branch's app.json or the orchestrator-supplied version. If unavailable, the dimension is unknown.
  • technologies — [al].
  • countries — the countries declared in the consuming app's app.json. If absent, unknown.
  • application-area — pass the actual set declared by the changed objects; do not substitute [all].

Discard files that are not applicable. Retain conditionally applicable files only when the orchestrator's configuration permits them; findings derived from those files MUST have confidence no higher than medium and MUST name the unknown dimensions in message.

Worklist

Narrow the relevant files to the subset that applies to the changes under review. For each relevant file, compute overlap against:

  • Changed AL objects — especially API pages (PageType = API), tables and pages declaring Labels/TextConsts, codeunits issuing Error/Message/Confirm, and any file whose name violates the <ObjectName>.<ObjectType>.al convention.
  • Changed declarations, weighted toward : Label '...', : TextConst '...', temporary record variables, option fields, DateFormula declarations and their Evaluate call sites, error-handling call sites, API declarations, and codeunit-internal method calls.
  • Tokens extracted from the diff (Label, TextConst, Locked, Comment, MaxLength, temporary, DateFormula, Evaluate, CalcDate, OptionMembers, OptionCaption, APIPublisher, APIGroup, APIVersion, EntityName, EntitySetName, DelayedInsert, FieldCaption, TableCaption, FieldName, TableName, Page.RunModal, Report.Run, this., StrSubstNo, namespace, using, var ).

A file enters the candidate worklist when its keywords intersect the extracted tokens or its topic (derived from the index entry's path, title, and description) matches a changed object or declaration. Read an article's full file — its ## Best Practice / ## Anti Pattern bodies — only after it makes the worklist; candidate selection uses the index alone.

Do not worklist temporary-variable-temp-prefix.md for an event publisher parameter. events/prefix-temporary-record-event-parameters-with-temp.md is the exclusive owner of that shape.

Apply these high-signal mappings before fuzzy topic ranking:

  • A Label or TextConst contains multiple or ambiguous placeholders but has no Comment, or its Comment does not explain every placeholder — label-comment-explains-placeholders.md. A single placeholder whose meaning is explicit in the text, such as Customer %1, is allowed without a Comment and must not be flagged.
  • A normal two-argument Evaluate has a resolved DateFormula destination and a hard-coded non-angle-bracket date-formula literal, directly or through a visible constant — dateformula-evaluate-needs-language-independent-literals.md. Do not use this cue for dynamic/localized external input, already invariant <...> input, or direct CalcDate(Text, ...) calls.
  • function-call-parentheses-required.md applies only to a zero-argument invocation written without (). Never worklist it from an invocation that already has parentheses or supplies arguments, including Error(Label, Arg1, Arg2).
  • A new .app build artifact appears at the project root or another unversioned/arbitrary location, or is added to source control alongside the AL source that produced it — al-build-output-must-not-pollute-project-root.md. A deliberate --outfolder/outputPath destination added to .gitignore is the compliant shape, not the signal to flag.
  • A new or renamed AL identifier (variable, procedure, parameter, field, object, enum value, or label identifier) contains non-English words — al-identifiers-english.md. A caption, tooltip, or other user-facing text value in a non-English language is not this anti-pattern; only the identifier itself is in scope.
  • A field or variable is typed Boolean and its two possible values are genuinely named domain alternatives (a status pair like Inbound/Outbound, Debit/Credit, Buy/Sell) rather than a true/false predicate, or an Option/Enum/Integer models a domain concept that is intrinsically a yes/no flag — binary-choice-must-be-boolean.md. The signal is a semantic mismatch between the type and the domain concept, not the current number of states.
  • A field or variable is typed Integer with the meaning of each value tracked only in a comment, or an Enum with more than two members is proposed as Boolean-like — fixed-choice-set-must-use-enum-not-integer.md. Do not flag a genuinely two-state Enum/Option for having "too few" members; that overlaps binary-choice-must-be-boolean.md instead when the domain is a true/false predicate.
  • A new using directive is added for an existing AL object without the diff also showing that object's own namespace declaration or a symbol-package lookup backing the choice — namespace-must-be-verified-from-source.md. Require repository/dependency context; a single new using line cannot itself prove whether the namespace was verified or guessed.
  • An intrinsic/built-in AL function call (MESSAGE, ERROR, CONFIRM, STRSUBSTNO, etc.) is written in ALL-CAPS or another non-PascalCase form — intrinsic-al-functions-must-use-modern-casing.md.
  • A procedure call passes a literal or a computed expression (not a caller-scope variable) to a parameter position the callee declares var — var-parameters-require-an-addressable-variable.md. This is a compile-time-guaranteed shape; flag it only when the callee's declared signature is visible in the diff or resolvable from context.

Once the candidate worklist is known, resolve layer-precedence conflicts per READ and record suppressions.

When the post-conflict worklist is empty because no applicable style knowledge exists, or because configuration suppressed every candidate, emit outcome: "no-knowledge". When the worklist is empty because no applicable style knowledge matched the changes, emit outcome: "completed" with an empty findings array.

Action

For each worklist entry, evaluate the diff against the file's ## Best Practice and ## Anti Pattern sections. Style findings rarely reach blocker — reserve it for cases where the knowledge file documents a platform-level requirement (for example, API page property constraints the OData runtime rejects). Most style findings are minor or info; egregious misuse (Error with pre-built Text losing translation and telemetry classification) may reach major.

Severity calibration — reserve minor for style issues with concrete downstream impact that deterministic tooling does not establish, such as lost translation or telemetry classification from a string-built Error or a misleading named invocation. A procedure-local Label is valid and is not a correctness or localization finding; an explicit repository preference for object scope is at most low-severity maintainability guidance. Do not rediscover or report mechanical compiler or analyzer diagnostics, even at info.

Set confidence to:

  • high when the detection is based on an unambiguous pattern match.
  • medium when detection relies on heuristics or when any frontmatter dimension was unknown.
  • low when the finding is an advisory derived only from applicability.

After evaluating each worklist entry, also consider whether the diff exhibits a style defect the agent recognises from its general AL knowledge that no knowledge file in the worklist covers. Such candidates are agent findings within this skill's domain — emit them with references: [], an id slug prefixed with agent:, confidence capped at medium, severity capped at minor (agent findings are advisory and non-gating), and a message that is self-contained (describing both the issue and a concrete recommendation, since there is no knowledge-file footer for the consumer to fall back on). Hold every candidate to the precision bar in skills/do.md (Agent findings): emit only a clear, widely-accepted AL style violation with a concrete basis a knowledgeable BC reviewer would agree on — steelman it first and drop personal preference, speculation, and any single defensible formatting choice among several; when in doubt, omit. The scope is strictly style — naming, labelling, formatting, and analyzer-adjacent conventions. A correctness, logic, data-integrity, or contract defect is NOT a style finding even when it can be reworded as a convention: a method that mutates a shared Record's filters, an unfiltered DeleteAll, a violated interface contract, or a wrong boolean guard are behavioural defects, not conventions — do not emit them here under a style framing. If a specific domain leaf covers the concern (performance, security, error-handling, …) it belongs there; if no knowledge file in any domain covers it, it belongs to the al-code-review super-skill's cross-cutting self-review agent channel (from-sub-skill: "agent", severity capped at minor), not to this leaf. A reliable test: if you cannot cite a style ## Best Practice/## Anti Pattern for the concern, it is very likely not a style finding. Before emitting, check the worklist for a knowledge file that matches the candidate — if one exists, upgrade the candidate to a knowledge-backed finding instead. See skills/do.md for the full contract.

For every emitted finding, decide whether the fix is mechanical. A fix is mechanical when it is small, local, and unambiguous from the diff context (for example: add a missing contextual ToolTip, replace a string-concatenated Error with a Label-backed call, or correct an API naming property whose intended value is clear). For mechanical findings, emit findings[].suggested-code with the literal replacement for the source lines indicated by location. The payload must be a verbatim replacement — no diff markers, no fences, no commentary — that the consumer can render as a one-click suggestion. When a .good.al companion exists and the diff context matches the .bad.al shape, adapt the .good.al replacement into suggested-code.

Omit suggested-code only when the appropriate fix depends on context the skill cannot determine, when multiple defensible replacements exist, or when the fix spans non-contiguous code. If a finding is mechanical-looking but you omit suggested-code, set findings[].suggested-code-omission-reason to a short explanation. See skills/do.md for the full contract.

Outcome selection:

  • completed — the skill evaluated every worklist item.
  • no-knowledge — no applicable style knowledge survived filtering.
  • not-applicable — no AL changes in the diff.
  • partial — a budget was hit before the worklist was exhausted.
  • failed — an unrecoverable error occurred.

Output

Output conforms to the DO output contract. Every finding this skill emits MUST set findings[].domain to "Style". A populated example:

{
  "skill": { "id": "al-style-review", "version": 1 },
  "outcome": "completed",
  "summary": {
    "counts": { "blocker": 0, "major": 0, "minor": 1, "info": 0 },
    "coverage": { "worklist-size": 1, "items-evaluated": 1 }
  },
  "findings": [
    {
      "id": "microsoft/knowledge/style/label-comment-explains-placeholders.md",
      "severity": "minor",
      "message": "The label has two ambiguous placeholders but no Comment explaining what each value represents to translators.",
      "location": {
        "file": "src/Sales/PostingRoutines.Codeunit.al",
        "line": 42
      },
      "references": [
        { "path": "microsoft/knowledge/style/label-comment-explains-placeholders.md" }
      ],
      "confidence": "high",
      "domain": "Style"
    }
  ],
  "suppressed": []
}