Improve error messages

src/combination/list/main.js

@@ -28,13 +28,16 @@ export const listCombinations = async function ({
 }
 
 // Get cartesian product of all combinations
+// `taskPath` is not set in `dimensions.task.path` because it used by the `init`
+// stage before task dimension ids are known.
 const getCombinationsProduct = function ({ tasks, inputs, systemId }) {
   if (tasks.length === 0) {
     throw new UserError(`Please specify some "tasks".`)
   }
 
-  return tasks.map(({ id, path, runner }) => ({
-    dimensions: { task: { id, path }, runner, system: { id: systemId } },
+  return tasks.map(({ id, taskPath, runner }) => ({
+    dimensions: { task: { id }, runner, system: { id: systemId } },
+    taskPath,
     inputs,
     stats: {},
   }))

src/combination/tasks/find.js

@@ -10,25 +10,25 @@ import { measureCombinations } from '../../run/measure/main.js'
 //    to several tasks competing for optimization in the same process
 // So we spawn a single process for all of them, to retrieve the task and step
 // identifiers.
-export const findTasks = async function (path, cwd, runner) {
-  await validateTask(path)
+export const findTasks = async function (taskPath, cwd, runner) {
+  await validateTask(taskPath)
 
   try {
     const [{ taskIds: ids }] = await measureCombinations(
-      [{ dimensions: { task: { path }, runner }, inputs: [] }],
+      [{ dimensions: { runner }, taskPath, inputs: [] }],
       { precisionTarget: 0, cwd, previewState: { quiet: true }, stage: 'init' },
     )
     validateDuplicateTaskIds(ids)
-    return ids.map((id) => ({ id, path, runner }))
+    return ids.map((id) => ({ id, taskPath, runner }))
   } catch (error) {
-    error.message = `In tasks file "${path}" (runner "${runner.id}")\n${error.message}`
+    error.message = `In tasks file "${taskPath}":\n${error.message}`
     throw error
   }
 }
 
-const validateTask = async function (path) {
-  if (!(await isFile(path))) {
-    throw new UserError(`Tasks file does not exist: ${path}`)
+const validateTask = async function (taskPath) {
+  if (!(await isFile(taskPath))) {
+    throw new UserError(`Tasks file does not exist: ${taskPath}`)
   }
 }
 

src/run/measure/events.js

@@ -19,13 +19,15 @@ export const runEvents = async function ({ combination, ...args }) {
 }
 
 // Start combination, i.e. make it load the combination and run any
-// runner-defined start logic
+// runner-defined start logic.
+// `task.id` is `undefined` during `init` stage.
 const startCombination = async function (
   {
     dimensions: {
-      task: { id, path },
+      task: { id } = {},
       runner: { config },
     },
+    taskPath,
     inputs,
   },
   server,
@@ -36,7 +38,7 @@ const startCombination = async function (
       event: 'start',
       runnerConfig: config,
       taskId: id,
-      taskPath: path,
+      taskPath,
       inputs: inputsObj,
     },
     server,

src/run/measure/single.js

@@ -100,18 +100,18 @@ const handleErrorsAndMeasure = async function ({
     throwIfStopped(stopState)
     return returnValue
   } catch (error) {
-    prependCombinationPrefix(error, args.combination, args.stage)
+    prependCombinationPrefix(error, args.combination)
     throw error
   }
 }
 
-const prependCombinationPrefix = function (error, combination, stage) {
-  if (stage === 'init' || error.name === 'StopError') {
+const prependCombinationPrefix = function (error, combination) {
+  if (error.name === 'StopError') {
     return
   }
 
   const combinationPrefix = getCombinationPrefix(combination)
-  error.message = `In ${combinationPrefix}\n${error.message}`
+  error.message = `In ${combinationPrefix}:\n${error.message}`
 }
 
 const getCombinationPrefix = function (combination) {