refactor!: make the codebase smaller and gate on duplication and test-only code

.jscpd.json

@@ -0,0 +1,8 @@
+{
+  "path": ["src"],
+  "format": ["typescript"],
+  "minLines": 6,
+  "threshold": 0.25,
+  "reporters": ["console"],
+  "gitignore": true
+}

CONTRIBUTING.md

@@ -28,8 +28,10 @@ npm test                # the vitest suite
 npm run gate            # everything a change has to pass before it is handed over
 ```
 
-`npm run gate` builds, runs knip and the tests, the isomorphism check of the browser-safe core, the
-layout-regression budget and a short fuzz campaign. CI runs `typecheck` and `gate` on every pull
+`npm run gate` builds, runs knip twice (the second time in production mode: code in `src/` that only
+tests use fails unless its export is tagged `@internal`), the duplication budget of `src/` (jscpd,
+`.jscpd.json`), the tests, the isomorphism check of the browser-safe core, the layout-regression
+budget and a short fuzz campaign. CI runs `typecheck` and `gate` on every pull
 request and every push to `main`. The test layers, the benchmark and the fuzzer, and how to run
 them on a private corpus without copying it into the repository, are described in
 [docs/testing.md](docs/testing.md).
@@ -60,7 +62,7 @@ them on a private corpus without copying it into the repository, are described i
   | `adapters/in/cli/` | the driving adapter: the `Cli` (commander, streams, exit codes, errors) and one class per command; it knows the use cases only by their contracts |
   | `adapters/in/report/` | what a use case's result looks like to the one who asked: text and JSON reports (`MutationText`, `MutationReportBuilder`, `ValidationText`, ...), the views as text, and the reference the guide and `bpmn kinds` print; the CLI prints them and `index.ts` / `api.ts` return them |
   | `adapters/out/files/` | the driven adapters on disk, Node only: `FileDocumentStore`, `BpmnlintProjectSettings`, `FileImageWriter` (PNG) |
-  | `adapters/out/memory/` | the driven adapters of the in-memory API: `InMemoryDocumentStore`, `NoProjectSettings` |
+  | `adapters/out/memory/` | the driven adapters of the in-memory API: `NoDocumentFiles`, `NoProjectSettings` |
   | `types/` | type shims for the bpmn-io packages that ship no usable declarations |
 
   Where new code goes: a new command is a type in `domain/commands/` and a `...Service` of the

docs/architecture.md

@@ -23,7 +23,7 @@ flowchart TB
   service --> domain["Domain<br/>domain/"]
   service --> portOut{{"Port<br/>application/port/out"}}
   portOut --> files["Files<br/>adapters/out/files"]
-  portOut --> memory["No project<br/>adapters/out/memory"]
+  portOut --> memory["No project, no files<br/>adapters/out/memory"]
 
   classDef adapter stroke:#2f80ed,stroke-width:2px
   classDef app stroke:#f2994a,stroke-width:2px
@@ -100,23 +100,21 @@ export class AddElementCommand extends MutationCommand {
     options: RawOpts,
   ) {
     const opts = this.mutationOptions(options)
-    await this.cli.guarded(async () => {
-      this.checkPlacementFlags(options)
-      const op: AddElement = {
-        op: 'add',
-        kind,                       // 'userTask'
-        name,                       // 'Check invoice'
-        after: options['after'],    // 'Event_OrderReceived'
-        // …
-      }
-      await this.mutate(file, [op], opts)
-    }, opts.json)
+    this.checkPlacementFlags(options)
+    const op: AddElement = {
+      op: 'add',
+      kind,                       // 'userTask'
+      name,                       // 'Check invoice'
+      after: options['after'],    // 'Event_OrderReceived'
+      // …
+    }
+    await this.mutate(file, [op], opts)
   }
 }
 ```
 
-`guarded()` catches any error and prints it with its code and hint. From here on nobody knows
-about flags any more.
+An error thrown here reaches `Cli.run`, which prints it with its code and hint. From here on
+nobody knows about flags any more.
 
 ### 2. Through the port
 
@@ -158,44 +156,33 @@ export declare namespace EditDocumentUseCase {
 ### 3. Load, run, save
 
 The service is short on purpose: get the document, let the domain work, write the result.
-`settings`, `load` and `save` are outbound ports, handed in by the constructor; without `load`
-or `save` the service takes only a document and writes nothing.
+`settings`, `load` and `save` are outbound ports, handed in by the constructor. The call into
+the domain stands on a line of its own; reading and writing the file are small steps around it.
 
 ```ts
 // src/application/service/EditDocumentService.ts
 export class EditDocumentService implements EditDocumentUseCase {
   constructor(
     private readonly settings: LoadProjectSettingsPort,
-    private readonly load?: LoadDocumentPort,
-    private readonly save?: SaveDocumentPort,
+    private readonly load: LoadDocumentPort,
+    private readonly save: SaveDocumentPort,
   ) {}
 
-  async edit({ source, commands, ...opts }: EditDocumentUseCase.Command) {
-    // step 7: read the file
-    const doc = 'doc' in source
-      ? source.doc
-      : await Doc.fromXml(await this.loadPort(source.file).read(source.file), source.file)
-    const target = opts.out ?? doc.file
-
-    // the project's .bpmnlintrc, if any
-    const lint = await this.settings.lint(target, opts)
-
-    // step 4: the domain does the work
-    const batchOpts = lint.applyTo(opts, target)
-    const batch = new EditBatchService(doc, commands, batchOpts)
-    const result = await batch.run(target)
-
-    // step 7: write the file
-    if (!opts.dryRun) {
-      result.written = await this.savePort().save(target, result.xml, { … })
-    }
+  async edit(command: EditDocumentUseCase.Command) {
+    const { source, commands, ...opts } = command
+    const doc = await this.open(source, opts)            // step 7: read the file
+    const target = await this.targetOf(doc, opts)
+    const project = (await this.settings.lint(opts.file ?? target, opts)).applyTo(opts, target)
+    const result = await new EditBatchService(doc, commands, project).run(target)   // step 4: the domain
+    await this.write(result, doc, target, opts)          // step 7: write the file
     return result
   }
 }
 ```
 
 In the CLI the ports are a `FileDocumentStore` and `BpmnlintProjectSettings`; `applyToXml()`
-passes only `NoProjectSettings` and a `{ doc }` with `dryRun`, so nothing is read or written.
+passes `NoProjectSettings`, `NoDocumentFiles` and a `{ doc }` with `dryRun`, so nothing is read
+or written.
 
 ### 4. The batch
 

docs/testing.md

@@ -234,9 +234,7 @@ ending on a number that reads like a suffix (`Phase1To...` kept), a cut
 inside a word that keeps the numbers, a camelCase end without its first
 word, a suffix within the cap, none skipped, also on an id that names the
 anchor's kind, a file prefix or scope too long for the cap in every flow
-form, cut flows voting for their form, flows 0.6 cut still following their
-ends, also with `_100` and a leading separator, ends of any length cut
-fast: #31),
+form, cut flows voting for their form, ends of any length cut fast: #31),
 transliteration beyond German, the definitions id of `new`, and the warnings
 delta: platform findings counted, a shrinking `W_DUPLICATE_NAME`, a bridge
 that takes over a removed flow's id, warnings of a batch's final state, `new`
@@ -787,9 +785,9 @@ node bin/bpmn.js add file.bpmn task "X" --after <id> --render /tmp/png/after.png
 reviews and blind judging, render with real bpmn-js:
 
 ```
-tools/render.sh /tmp/png file1.bpmn file2.bpmn            # any files
+tools/bench/render.sh /tmp/png file1.bpmn file2.bpmn      # any files
 tools/bench/render.sh /tmp/png tools/bench/results/latest/work/edits/<arm>/<corpus>/<model>/*/model.bpmn
 ```
 
-Both need Google Chrome (`PUPPETEER_EXECUTABLE_PATH` overrides the macOS
-default path) and fetch `bpmn-to-image` with npx.
+It needs Google Chrome (`PUPPETEER_EXECUTABLE_PATH` overrides the macOS
+default path) and fetches `bpmn-to-image` with npx.

knip.json

@@ -1,6 +1,6 @@
 {
   "$schema": "https://unpkg.com/knip@6/schema.json",
-  "entry": ["src/api.ts", "tools/**/*.mjs", "test/**/*.test.ts"],
-  "project": ["src/**/*.ts", "tools/**/*.mjs", "test/**/*.ts"],
-  "ignoreDependencies": ["@resvg/resvg-wasm", "playwright"]
+  "entry": ["src/api.ts!", "tools/**/*.mjs", "test/**/*.test.ts"],
+  "project": ["src/**/*.ts!", "tools/**/*.mjs", "test/**/*.ts"],
+  "ignoreDependencies": ["@resvg/resvg-wasm"]
 }

package.json

@@ -61,7 +61,7 @@
     "docs:dev": "npm --prefix docs run dev",
     "docs:build": "npm --prefix docs run build",
     "docs:preview": "npm --prefix docs run preview",
-    "gate": "npm run build && knip && vitest run && node tools/iso/check.mjs && node tools/bench/regress-gate.mjs && node tools/fuzz/run.mjs --walks 12 --steps 15 --seed 1 --hard warn --out tools/fuzz/out/gate",
+    "gate": "npm run build && knip && knip --production --exclude dependencies && jscpd && vitest run && node tools/iso/check.mjs && node tools/bench/regress-gate.mjs && node tools/fuzz/run.mjs --walks 12 --steps 15 --seed 1 --hard warn --out tools/fuzz/out/gate",
     "prepublishOnly": "npm run build"
   },
   "dependencies": {
@@ -78,8 +78,8 @@
     "archunit": "2.5.4",
     "camunda-bpmn-moddle": "8.0.2",
     "esbuild": "^0.28.2",
+    "jscpd": "5.4.1",
     "knip": "6.43.0",
-    "playwright": "1.64.1",
     "tsx": "^4.23.0",
     "typescript": "^7.0.2",
     "vitest": "^5.0.2",