Improve build resolver for fixing some edge cases (#988)

server/build.go

@@ -41,6 +41,7 @@ type BuildContext struct {
 	wd          string
 	pkgJson     *PackageJSON
 	path        string
+	rawPath     string
 	status      string
 	splitting   *set.ReadOnlySet[string]
 	esmImports  [][2]string
@@ -98,57 +99,7 @@ func (ctx *BuildContext) Path() string {
 		return ctx.path
 	}
 
-	asteriskPrefix := ""
-	if ctx.externalAll {
-		asteriskPrefix = "*"
-	}
-
-	esm := ctx.esm
-	if ctx.target == "types" {
-		if strings.HasSuffix(esm.SubPath, ".d.ts") {
-			ctx.path = fmt.Sprintf(
-				"/%s%s/%s%s",
-				asteriskPrefix,
-				esm.Name(),
-				ctx.getBuildArgsPrefix(true),
-				esm.SubPath,
-			)
-		} else {
-			ctx.path = "/" + esm.Specifier()
-		}
-		return ctx.path
-	}
-
-	name := strings.TrimSuffix(path.Base(esm.PkgName), ".js")
-	if esm.SubModuleName != "" {
-		if esm.SubModuleName == name {
-			// if the sub-module name is same as the package name
-			name = "__" + esm.SubModuleName
-		} else {
-			name = esm.SubModuleName
-		}
-		// workaround for es5-ext "../#/.." path
-		if esm.PkgName == "es5-ext" {
-			name = strings.ReplaceAll(name, "/#/", "/%23/")
-		}
-	}
-
-	if ctx.dev {
-		name += ".development"
-	}
-	if ctx.bundleMode == BundleAll {
-		name += ".bundle"
-	} else if ctx.bundleMode == BundleFalse {
-		name += ".nobundle"
-	}
-	ctx.path = fmt.Sprintf(
-		"/%s%s/%s%s/%s.mjs",
-		asteriskPrefix,
-		esm.Name(),
-		ctx.getBuildArgsPrefix(ctx.target == "types"),
-		ctx.target,
-		name,
-	)
+	ctx.buildPath()
 	return ctx.path
 }
 
@@ -232,6 +183,60 @@ func (ctx *BuildContext) Build() (meta *BuildMeta, err error) {
 	return
 }
 
+func (ctx *BuildContext) buildPath() {
+	asteriskPrefix := ""
+	if ctx.externalAll {
+		asteriskPrefix = "*"
+	}
+
+	esm := ctx.esm
+	if ctx.target == "types" {
+		if strings.HasSuffix(esm.SubPath, ".d.ts") {
+			ctx.path = fmt.Sprintf(
+				"/%s%s/%s%s",
+				asteriskPrefix,
+				esm.Name(),
+				ctx.getBuildArgsPrefix(true),
+				esm.SubPath,
+			)
+		} else {
+			ctx.path = "/" + esm.Specifier()
+		}
+		return
+	}
+
+	name := strings.TrimSuffix(path.Base(esm.PkgName), ".js")
+	if esm.SubModuleName != "" {
+		if esm.SubModuleName == name {
+			// if the sub-module name is same as the package name
+			name = "__" + esm.SubModuleName
+		} else {
+			name = esm.SubModuleName
+		}
+		// workaround for es5-ext "../#/.." path
+		if esm.PkgName == "es5-ext" {
+			name = strings.ReplaceAll(name, "/#/", "/%23/")
+		}
+	}
+
+	if ctx.dev {
+		name += ".development"
+	}
+	if ctx.bundleMode == BundleAll {
+		name += ".bundle"
+	} else if ctx.bundleMode == BundleFalse {
+		name += ".nobundle"
+	}
+	ctx.path = fmt.Sprintf(
+		"/%s%s/%s%s/%s.mjs",
+		asteriskPrefix,
+		esm.Name(),
+		ctx.getBuildArgsPrefix(ctx.target == "types"),
+		ctx.target,
+		name,
+	)
+}
+
 func (ctx *BuildContext) buildModule(analyzeMode bool) (meta *BuildMeta, includes [][2]string, err error) {
 	entry := ctx.resolveEntry(ctx.esm)
 	if entry.isEmpty() {
@@ -1443,10 +1448,9 @@ func (ctx *BuildContext) buildTypes() (ret *BuildMeta, err error) {
 
 func (ctx *BuildContext) install() (err error) {
 	if ctx.wd == "" || ctx.pkgJson == nil {
-		var p *PackageJSON
-		p, err = ctx.npmrc.installPackage(ctx.esm.Package())
+		p, err := ctx.npmrc.installPackage(ctx.esm.Package())
 		if err != nil {
-			return
+			return err
 		}
 
 		if ctx.esm.GhPrefix || ctx.esm.PrPrefix {
@@ -1491,6 +1495,7 @@ func (ctx *BuildContext) install() (err error) {
 			if isMainModule {
 				ctx.esm.SubModuleName = ""
 				ctx.esm.SubPath = ""
+				ctx.rawPath = ctx.path
 				ctx.path = ""
 			}
 		}

server/build_queue.go

@@ -110,6 +110,10 @@ func (q *BuildQueue) run(task *BuildTask) {
 	q.lock.Lock()
 	q.queue.Remove(task.el)
 	delete(q.tasks, task.ctx.Path())
+	if task.ctx.rawPath != "" {
+		// the `Build` function may have changed the path
+		delete(q.tasks, task.ctx.rawPath)
+	}
 	q.chann += 1
 	q.lock.Unlock()
 

server/build_resolver.go

@@ -80,22 +80,43 @@ func (ctx *BuildContext) resolveEntry(esm EsmPath) (entry BuildEntry) {
 		// reslove sub-module using `exports` conditions if exists
 		// see https://nodejs.org/api/packages.html#package-entry-points
 		if pkgJson.Exports.Len() > 0 {
-			exportEntry := BuildEntry{}
-			for _, name := range pkgJson.Exports.keys {
-				conditions, ok := pkgJson.Exports.values[name]
-				if ok {
-					if name == "./"+subModuleName || stripEntryModuleExt(name) == "./"+subModuleName {
+			var exportEntry BuildEntry
+			conditions, ok := pkgJson.Exports.Get("./" + subModuleName)
+			if ok {
+				if s, ok := conditions.(string); ok {
+					/**
+					exports: {
+						"./lib/foo": "./lib/foo.js"
+					}
+					*/
+					exportEntry.update(s, pkgJson.Type == "module")
+				} else if obj, ok := conditions.(JSONObject); ok {
+					/**
+					exports: {
+						"./lib/foo": {
+							"require": "./lib/foo.js",
+							"import": "./esm/foo.js",
+							"types": "./types/foo.d.ts"
+						}
+					}
+					*/
+					exportEntry = ctx.resolveConditionExportEntry(obj, pkgJson.Type)
+				}
+			} else {
+				for _, name := range pkgJson.Exports.keys {
+					conditions := pkgJson.Exports.values[name]
+					if stripEntryModuleExt(name) == "./"+subModuleName {
 						if s, ok := conditions.(string); ok {
 							/**
 							exports: {
-								"./lib/foo": "./lib/foo.js"
+								"./lib/foo.js": "./lib/foo.js"
 							}
 							*/
 							exportEntry.update(s, pkgJson.Type == "module")
 						} else if obj, ok := conditions.(JSONObject); ok {
 							/**
 							exports: {
-								"./lib/foo": {
+								"./lib/foo.js": {
 									"require": "./lib/foo.js",
 									"import": "./esm/foo.js",
 									"types": "./types/foo.d.ts"

server/router.go

@@ -186,25 +186,27 @@ func esmRouter() rex.Handle {
 		}
 
 		// strip trailing slash
-		if last := len(pathname) - 1; pathname != "/" && pathname[last] == '/' {
-			pathname = pathname[:last]
+		if pl := len(pathname); pl > 1 && pathname[pl-1] == '/' {
+			pathname = pathname[:pl-1]
 		}
 
 		// strip loc suffix
 		// e.g. https://esm.sh/react/es2022/react.mjs:2:3
-		i := len(pathname) - 1
-		j := 0
-		for {
-			if i < 0 || pathname[i] == '/' {
-				break
+		{
+			i := len(pathname) - 1
+			j := 0
+			for {
+				if i < 0 || pathname[i] == '/' {
+					break
+				}
+				if pathname[i] == ':' {
+					j = i
+				}
+				i--
 			}
-			if pathname[i] == ':' {
-				j = i
+			if j > 0 {
+				pathname = pathname[:j]
 			}
-			i--
-		}
-		if j > 0 {
-			pathname = pathname[:j]
 		}
 
 		// static routes
@@ -1612,7 +1614,7 @@ func esmRouter() rex.Handle {
 			if !ret.HasCSS {
 				return rex.Status(404, "Package CSS not found")
 			}
-			url := fmt.Sprintf("%s%s.css", origin, strings.TrimSuffix(buildCtx.Path(), ".mjs"))
+			url := origin + strings.TrimSuffix(buildCtx.Path(), ".mjs") + ".css"
 			return redirect(ctx, url, isExactVersion)
 		}
 
@@ -1631,6 +1633,18 @@ func esmRouter() rex.Handle {
 
 		// if the path is `ESMBuild`, return the built js/css content
 		if pathKind == EsmBuild {
+			// if the build
+			if esm.SubPath != buildCtx.esm.SubPath {
+				buf, recycle := NewBuffer()
+				defer recycle()
+				fmt.Fprintf(buf, "export * from \"%s\";\n", buildCtx.Path())
+				if ret.ExportDefault {
+					fmt.Fprintf(buf, "export { default } from \"%s\";\n", buildCtx.Path())
+				}
+				ctx.Header.Set("Content-Type", ctJavaScript)
+				ctx.Header.Set("Cache-Control", ccImmutable)
+				return buf.Bytes()
+			}
 			savePath := buildCtx.getSavepath()
 			if strings.HasSuffix(esm.SubPath, ".css") {
 				path, _ := utils.SplitByLastByte(savePath, '.')

test/fix-url/test.ts

@@ -145,3 +145,11 @@ Deno.test("dts-transformer: support `.d` extension", async () => {
   const dts = await res.text();
   assertStringIncludes(dts, "'./config.d.ts'");
 });
+
+Deno.test("fix rewritten build path", async () => {
+  for (let i = 0; i < 2; i++) {
+    const res = await fetch("http://localhost:8080/@ucanto/[email protected]/denonext/src/lib.mjs");
+    const js = await res.text();
+    assertEquals(js.trim(), `export * from "/@ucanto/[email protected]/denonext/core.mjs";`);
+  }
+});

test/issue-787/test.ts

@@ -0,0 +1,8 @@
+import { assertExists } from "jsr:@std/assert";
+
+import * as capabilities from "http://localhost:8080/@web3-storage/capabilities@^18.0.0/index?target=denonext";
+
+Deno.test("issue #787", () => {
+  assertExists(capabilities.add);
+  assertExists(capabilities.add.can);
+});