perf(ngcc): only compute basePaths in TargetedEntryPointFinder when needed (#36881)

Previously the `basePaths` were computed when the finder was instantiated.
This was a waste of effort in the case that the targeted entry-point is already
processed.

This change makes the computation of `basePaths` lazy, so that the work is
only done if they are actually needed.

Fixes #36874

PR Close #36881
This commit is contained in:
Pete Bacon Darwin 2020-05-01 10:13:30 +01:00 committed by Alex Rickabaugh
parent db4c59dad9
commit ec6b9cc17d
1 changed files with 78 additions and 44 deletions

View File

@ -27,7 +27,13 @@ import {getBasePaths} from './utils';
export class TargetedEntryPointFinder implements EntryPointFinder {
private unprocessedPaths: AbsoluteFsPath[] = [];
private unsortedEntryPoints = new Map<AbsoluteFsPath, EntryPointWithDependencies>();
private basePaths = getBasePaths(this.logger, this.basePath, this.pathMappings);
private basePaths: AbsoluteFsPath[]|null = null;
private getBasePaths() {
if (this.basePaths === null) {
this.basePaths = getBasePaths(this.logger, this.basePath, this.pathMappings);
}
return this.basePaths;
}
constructor(
private fs: FileSystem, private config: NgccConfiguration, private logger: Logger,
@ -102,50 +108,24 @@ export class TargetedEntryPointFinder implements EntryPointFinder {
return entryPoint;
}
/**
* Search down to the `entryPointPath` from each `basePath` for the first `package.json` that we
* come to. This is the path to the entry-point's containing package. For example if `basePath` is
* `/a/b/c` and `entryPointPath` is `/a/b/c/d/e` and there exists `/a/b/c/d/package.json` and
* `/a/b/c/d/e/package.json`, then we will return `/a/b/c/d`.
*
* To account for nested `node_modules` we actually start the search at the last `node_modules` in
* the `entryPointPath` that is below the `basePath`. E.g. if `basePath` is `/a/b/c` and
* `entryPointPath` is `/a/b/c/d/node_modules/x/y/z`, we start the search at
* `/a/b/c/d/node_modules`.
*/
private computePackagePath(entryPointPath: AbsoluteFsPath): AbsoluteFsPath {
for (const basePath of this.basePaths) {
// First try the main basePath, to avoid having to compute the other basePaths from the paths
// mappings, which can be computationally intensive.
if (entryPointPath.startsWith(this.basePath)) {
const packagePath = this.computePackagePathFromContainingPath(entryPointPath, this.basePath);
if (packagePath !== null) {
return packagePath;
}
}
// The main `basePath` didn't work out so now we try the `basePaths` computed from the paths
// mappings in `tsconfig.json`.
for (const basePath of this.getBasePaths()) {
if (entryPointPath.startsWith(basePath)) {
let packagePath = basePath;
const segments = this.splitPath(relative(basePath, entryPointPath));
let nodeModulesIndex = segments.lastIndexOf(relativeFrom('node_modules'));
// If there are no `node_modules` in the relative path between the `basePath` and the
// `entryPointPath` then just try the `basePath` as the `packagePath`.
// (This can be the case with path-mapped entry-points.)
if (nodeModulesIndex === -1) {
if (this.fs.exists(join(packagePath, 'package.json'))) {
return packagePath;
}
const packagePath = this.computePackagePathFromContainingPath(entryPointPath, basePath);
if (packagePath !== null) {
return packagePath;
}
// Start the search at the deepest nested `node_modules` folder that is below the `basePath`
// but above the `entryPointPath`, if there are any.
while (nodeModulesIndex >= 0) {
packagePath = join(packagePath, segments.shift()!);
nodeModulesIndex--;
}
// Note that we start at the folder below the current candidate `packagePath` because the
// initial candidate `packagePath` is either a `node_modules` folder or the `basePath` with
// no `package.json`.
for (const segment of segments) {
packagePath = join(packagePath, segment);
if (this.fs.exists(join(packagePath, 'package.json'))) {
return packagePath;
}
}
// If we got here then we couldn't find a `packagePath` for the current `basePath`.
// Since `basePath`s are guaranteed not to be a sub-directory of each other then no other
// `basePath` will match either.
@ -153,8 +133,62 @@ export class TargetedEntryPointFinder implements EntryPointFinder {
}
}
// We couldn't find a `packagePath` using `basePaths` so try to find the nearest `node_modules`
// that contains the `entryPointPath`, if there is one, and use it as a `basePath`.
// Finally, if we couldn't find a `packagePath` using `basePaths` then try to find the nearest
// `node_modules` that contains the `entryPointPath`, if there is one, and use it as a
// `basePath`.
return this.computePackagePathFromNearestNodeModules(entryPointPath);
}
/**
* Search down to the `entryPointPath` from the `containingPath` for the first `package.json` that
* we come to. This is the path to the entry-point's containing package. For example if
* `containingPath` is `/a/b/c` and `entryPointPath` is `/a/b/c/d/e` and there exists
* `/a/b/c/d/package.json` and `/a/b/c/d/e/package.json`, then we will return `/a/b/c/d`.
*
* To account for nested `node_modules` we actually start the search at the last `node_modules` in
* the `entryPointPath` that is below the `containingPath`. E.g. if `containingPath` is `/a/b/c`
* and `entryPointPath` is `/a/b/c/d/node_modules/x/y/z`, we start the search at
* `/a/b/c/d/node_modules`.
*/
private computePackagePathFromContainingPath(
entryPointPath: AbsoluteFsPath, containingPath: AbsoluteFsPath): AbsoluteFsPath|null {
let packagePath = containingPath;
const segments = this.splitPath(relative(containingPath, entryPointPath));
let nodeModulesIndex = segments.lastIndexOf(relativeFrom('node_modules'));
// If there are no `node_modules` in the relative path between the `basePath` and the
// `entryPointPath` then just try the `basePath` as the `packagePath`.
// (This can be the case with path-mapped entry-points.)
if (nodeModulesIndex === -1) {
if (this.fs.exists(join(packagePath, 'package.json'))) {
return packagePath;
}
}
// Start the search at the deepest nested `node_modules` folder that is below the `basePath`
// but above the `entryPointPath`, if there are any.
while (nodeModulesIndex >= 0) {
packagePath = join(packagePath, segments.shift()!);
nodeModulesIndex--;
}
// Note that we start at the folder below the current candidate `packagePath` because the
// initial candidate `packagePath` is either a `node_modules` folder or the `basePath` with
// no `package.json`.
for (const segment of segments) {
packagePath = join(packagePath, segment);
if (this.fs.exists(join(packagePath, 'package.json'))) {
return packagePath;
}
}
return null;
}
/**
* Search up the directory tree from the `entryPointPath` looking for a `node_modules` directory
* that we can use as a potential starting point for computing the package path.
*/
private computePackagePathFromNearestNodeModules(entryPointPath: AbsoluteFsPath): AbsoluteFsPath {
let packagePath = entryPointPath;
let scopedPackagePath = packagePath;
let containerPath = this.fs.dirname(packagePath);