Propagation depth

This is the central setting. For each file you decide how far the run propagates through the reverse graph, meaning through the files that import it.

Try it#

Pick a depth and see, right now, what would happen when login.ts is saved. This runs the same breadth-first search the daemon runs.

Notice that self still runs a test. Propagation walks import edges; mapping a source file to its test file happens afterwards, by naming convention. Collapsing the two stages would make self run nothing at all, because the test sits one hop away from the source.

Configuring it#

{
  "dependencyDepth": {
    "default": "direct",
    "overrides": {
      "src/util/**": "self",                   // stable utility: does not propagate
      "src/components/Login.tsx": "transitive"  // critical: propagates all the way
    }
  }
}

Overrides are evaluated in declaration order, and the last match wins, which lets you write a broad rule followed by exceptions:

"overrides": {
  "src/**": "self",                         // general rule
  "src/components/Login.tsx": "transitive"  // exception
}

Choosing a value#

Too many tests running (slow). A file imported by half the project, like a types module or a constants file, drags the whole suite along on every save. Pin it to "self".

Too few tests running (regressions slip through). A file whose breakage shows up only in its consumers, typically authentication, routing or serialization, deserves "transitive".

Not sure. Leave "direct". It is the default because it catches the common case, the importer that broke, without paying for the full chain.

Checking before you commit to it#

$ npx livetest why src/login.ts

file:       src/login.ts
runner:     js
depth:      transitive, file plus the full chain of importers  [override: src/login.ts]

impacted files (8):
  [0] src/login.ts
  [1] src/header.ts
  [2] src/layout.ts via src/header.ts
  ...

You can also try a depth without editing the config file:

npx livetest run src/login.ts --depth transitive
npx livetest why src/login.ts --depth self