ts-transform-paths needs updating for TypeScript 4.5+

[Kadeluxe]

ts-transform-paths is broken for TypeScript 4.5+.
The reason is that import declarations nodes miss parent node and therefore TS is unable to determine source file of node (compiler/checker.ts, resolveExternalModule function).

I did a quick look and apparently setting newNode.parent to original node .parent fixes it (as you have done for export declarations).
Since I heavily rely on @zerollup/ts-transform-paths in my work, I created @Kadeluxe/ts-transform-paths repo with that fix and some other small changes.

I'm not creating PR here because I don't have much knowledge of TypeScript internals so I can't tell if it's the proper way to fix it. I guess this plugin may need further updating.

UPDATE: since there is no progress on this, I published my fork on NPM: https://www.npmjs.com/package/@kadeluxe/ts-transform-paths
Do npm i @kadeluxe/ts-transform-paths and replace @zerollup/ts-emit-import-alias with @kadeluxe/ts-emit-import-alias in your tsconfig.json. Now it will work.
Also you can switch to different transformer like https://github.com/LeDDGroup/typescript-transform-paths.

[falkenhawk]

@Kadeluxe could you instead fork this repo and add your fixes and changes in separate commits, please? Otherwise it is impossible to tell what and where your modifications are.

[Kadeluxe]

Well I didn't really want to bother with the whole monorepo but here you go:
https://github.com/Kadeluxe/zerollup/tree/master/packages/ts-transform-paths
Also published to GitHub Packages.

Again, I didn't really look much into internals, TypeScript has lots of changes since 3.7.2 which this transformers initially targets apparently but this change fixes compilation on TS 4.5 and I haven't noticed other issues yet.

[khitrenovich]

@zerkalica / @falkenhawk -
Thank you for maintaining ts-transform-paths!
Do you plan to release a patch that fixes TS 4.5 compatibility?

[Drapegnik]

hi! thanks!
I created patch with https://github.com/ds300/patch-package to temporarily fix it without fork:

just add this to patches/@zerollup+ts-transform-paths+1.7.18.patch file

diff --git a/node_modules/@zerollup/ts-transform-paths/dist/index.js b/node_modules/@zerollup/ts-transform-paths/dist/index.js
index e9da4bd..555f4af 100644
--- a/node_modules/@zerollup/ts-transform-paths/dist/index.js
+++ b/node_modules/@zerollup/ts-transform-paths/dist/index.js
@@ -169,7 +169,9 @@ function importPathVisitor(node, _a) {
         newNode.flags = node.flags;
     }
     if (ts.isImportDeclaration(node)) {
-        newNode = ts.updateImportDeclaration(node, node.decorators, node.modifiers, node.importClause, newSpec);
+        var importNode = ts.updateImportDeclaration(node, node.decorators, node.modifiers, node.importClause, newSpec);
+        importNode.moduleSpecifier.parent = node.moduleSpecifier.parent
+        newNode = importNode
         /**
          * Without this hack ts generates bad import of pure interface in output js,
          * this causes warning "module has no exports" in bundlers.

and following in your package.json

"postinstall": "patch-package"

[embryCODE]

@Drapegnik You, sir, are a gentleman and a scholar. Thanks for this timely fix.

[krisdages]

@Drapegnik Is that "if isImportDeclaration" branch the only one that's actually affected? What if you have an export { ... } from ""?

I should have looked here before trying to figure out the issue myself, but this was the change I made just before returning from that function that checks the node type.

patches/@zerollup+ts-transform-paths+1.7.18.patch file:

diff --git a/node_modules/@zerollup/ts-transform-paths/dist/index.js b/node_modules/@zerollup/ts-transform-paths/dist/index.js
index e9da4bd..10e9832 100644
--- a/node_modules/@zerollup/ts-transform-paths/dist/index.js
+++ b/node_modules/@zerollup/ts-transform-paths/dist/index.js
@@ -217,6 +217,10 @@ function importPathVisitor(node, _a) {
     if (ts.isModuleDeclaration(node)) {
         newNode = ts.updateModuleDeclaration(node, node.decorators, node.modifiers, newSpec, node.body);
     }
+    if (newNode) {
+        newSpec.parent = newNode
+        newNode.parent = node.parent
+    }
     return newNode;
 }
 

[Kadeluxe]

TypeScript compiler currently only needs parent for import declarations (starting with 4.5+) but yes, it may be "future-proof" to properly preserve newNode.parent for any cases.
Not sure how it affects the whole thing though, without deep knowledge of TypeScript internals it's hard to tell why TS doesn't preserve parent itself when you call update... compiler methods and what possible issues that may trigger overall.

[alexn-s]

hi! thanks! I created patch with https://github.com/ds300/patch-package to temporarily fix it without fork:

just add this to patches/@zerollup+ts-transform-paths+1.7.18.patch file

diff --git a/node_modules/@zerollup/ts-transform-paths/dist/index.js b/node_modules/@zerollup/ts-transform-paths/dist/index.js
index e9da4bd..555f4af 100644
--- a/node_modules/@zerollup/ts-transform-paths/dist/index.js
+++ b/node_modules/@zerollup/ts-transform-paths/dist/index.js
@@ -169,7 +169,9 @@ function importPathVisitor(node, _a) {
         newNode.flags = node.flags;
     }
     if (ts.isImportDeclaration(node)) {
-        newNode = ts.updateImportDeclaration(node, node.decorators, node.modifiers, node.importClause, newSpec);
+        var importNode = ts.updateImportDeclaration(node, node.decorators, node.modifiers, node.importClause, newSpec);
+        importNode.moduleSpecifier.parent = node.moduleSpecifier.parent
+        newNode = importNode
         /**
          * Without this hack ts generates bad import of pure interface in output js,
          * this causes warning "module has no exports" in bundlers.

and following in your package.json

"postinstall": "patch-package"

Awesome fix. worked perfectly.

thank you so much

[pmrotule]

Well I didn't really want to bother with the whole monorepo but here you go: https://github.com/Kadeluxe/zerollup/tree/master/packages/ts-transform-paths Also published to GitHub Packages.

@Kadeluxe Why not opening a PR? That would be very helpful.

[simmo]

@Drapegnik Is that "if isImportDeclaration" branch the only one that's actually affected? What if you have an export { ... } from ""?

I should have looked here before trying to figure out the issue myself, but this was the change I made just before returning from that function that checks the node type.

patches/@zerollup+ts-transform-paths+1.7.18.patch file:

diff --git a/node_modules/@zerollup/ts-transform-paths/dist/index.js b/node_modules/@zerollup/ts-transform-paths/dist/index.js
index e9da4bd..10e9832 100644
--- a/node_modules/@zerollup/ts-transform-paths/dist/index.js
+++ b/node_modules/@zerollup/ts-transform-paths/dist/index.js
@@ -217,6 +217,10 @@ function importPathVisitor(node, _a) {
     if (ts.isModuleDeclaration(node)) {
         newNode = ts.updateModuleDeclaration(node, node.decorators, node.modifiers, newSpec, node.body);
     }
+    if (newNode) {
+        newSpec.parent = newNode
+        newNode.parent = node.parent
+    }
     return newNode;
 }
 

I've raised a PR for this patch - #38