glm-5.1
bde1cc4e70
The 751-line architecture.md violated the SDD process modular documentation target (~500 lines). It also had duplicate TaskGraph class definitions (one monolith, one decomposed) that directly contradicted each other, and embedded consumer-specific tool dispatch mappings that belong in downstream projects. Changes: - Split into 8 focused documents + 7 ADR records + redirect page - Removed the monolithic TaskGraph class (kept only decomposed version) - Moved CLI→plugin dispatch mapping out (belongs in plugin architecture) - Extracted implementation code (frontmatter splitter, findCycles, DAG propagation) into WHAT/WHY descriptions per architect role spec - Added proper ADR format for all resolved design decisions - Fixed review issues: C_fail mapping, DuplicateNodeError/DuplicateEdgeError types, ValidationError/GraphValidationError definitions, mutation error handling contract, enum naming convention, validation timing clarification
25 lines
1.3 KiB
Markdown
25 lines
1.3 KiB
Markdown
# ADR-007: Subgraph returns internal-only edges
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**Status**: Accepted
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## Context
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When filtering a graph to a subset of nodes, what happens to edges where only one endpoint is in the filtered set? Options: include cross-boundary edges (external dependencies visible), or strict internal-only (only edges where both endpoints are in the filtered set).
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## Decision
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**Strict internal-only.** `subgraph(filter)` returns a new `TaskGraph` with matching nodes and only edges where both endpoints are in the filtered set. This matches `graphology-operators` `subgraph` behavior and produces valid subgraphs for all algorithms (topo sort, betweenness, etc.).
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## Consequences
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### Positive
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- Result is always a valid (potentially disconnected) subgraph — all algorithms work correctly
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- Matches graphology's built-in subgraph behavior
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- No surprise external references in analysis results
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### Negative
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- External dependency information is lost — you can't see "what does this subgraph depend on outside itself" from the subgraph alone
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### Mitigation
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External dependency information is available on the original graph via `dependencies()`/`dependents()`. A separate `externalDependencies(filter)` utility can be added later if consumers need "show me what this subgraph depends on outside itself." |