Class LibraryExtractionScanner

Library extraction scanner.

Finds artifacts in the target folders that could move into dedicated Angular libraries with secondary entry points:

Computes metrics per artifact (cross-folder importers resolved through barrels, spec file, external imports, barrel export, data-only file)
Keeps artifacts whose reusability score (location bonus, cross-module usage, public export, few dependencies, test evidence) reaches minReusabilityScore
Clusters them by LibraryCategory; large clusters are split by domain folder, data-only files form their own models cluster
Keeps clusters whose cohesion score reaches minCohesionScore and reports each as a LibraryExtractionOpportunity

Pure TypeScript weighted scoring, no external ML dependency.

Index

Constructors

Methods

calculateCohesionScore calculateReusabilityScore scan

Constructors

constructor

new LibraryExtractionScanner(
config?: Partial<LibraryExtractionScannerConfig>,
): LibraryExtractionScanner
Parameters
- config: Partial<LibraryExtractionScannerConfig> = {}
  Overrides of the default LibraryExtractionScannerConfig
Returns LibraryExtractionScanner

Methods

calculateCohesionScore

calculateCohesionScore(artifacts: ArtifactMetrics[]): number
Internal
Cohesion score = weighted average of:
- Location cohesion: % members in same/related folder (weight 0.5)
- Naming cohesion: % members sharing a common prefix/suffix (weight 0.3)
- Import cohesion: % members importing each other (weight 0.2)
Location is weighted highest: for library extraction, artifacts in the same shared folder belong in the same library regardless of whether they import each other (most UI components are independent by design).
Parameters
- artifacts: ArtifactMetrics[]
Returns number

calculateReusabilityScore

calculateReusabilityScore(metrics: ArtifactMetrics): number
Calculate reusability score (0-100).

Formula: score = locationBonus + crossModuleUsage * 0.3 + isPubliclyExported * 0.15 + minimalDependencies * 0.15 + hasTestFile * 0.1

locationBonus: 30 points for any file already placed in a shared/libs/common/core folder — the developer already decided it belongs there.

crossModuleUsage is normalized to min(count/3, 1): each additional importer above 1 increases the score (3+ usages = max contribution).

minimalDependencies = 1 - min(dependencyCount / 10, 1) — uses /10 instead of /5 so Angular components importing @angular/core etc. aren't penalised as heavily.

Data-only artifacts (interfaces / types / enums / consts) never have spec files, so their 10-point test slot is filled with importer evidence instead: min(crossModuleUsage / 5, 1). A model imported from 5+ other folders is as proven as a tested component.
Parameters
- metrics: ArtifactMetrics
Returns number

scan

scan(
context: AnalysisContext<PublicApi>,
): Promise<LibraryExtractionOpportunity[]>
Scan all source files in the context's project for library extraction opportunities.
Parameters
- context: AnalysisContext<PublicApi>
Returns Promise<LibraryExtractionOpportunity[]>