use xxHash instead of SHA1 for speed (#1107)

internal/bundler/bundler.go

@@ -2,7 +2,6 @@ package bundler
 
 import (
 	"bytes"
-	"crypto/sha1"
 	"encoding/base32"
 	"encoding/base64"
 	"fmt"
@@ -31,6 +30,7 @@ import (
 	"github.com/evanw/esbuild/internal/resolver"
 	"github.com/evanw/esbuild/internal/runtime"
 	"github.com/evanw/esbuild/internal/sourcemap"
+	"github.com/evanw/esbuild/internal/xxhash"
 )
 
 type entryPointKind uint8
@@ -342,8 +342,9 @@ func parseFile(args parseArgs) {
 		// but different contents from colliding
 		var hash string
 		if config.HasPlaceholder(args.options.AssetPathTemplate, config.HashPlaceholder) {
-			hashBytes := sha1.Sum([]byte(source.Contents))
-			hash = hashForFileName(hashBytes)
+			h := xxhash.New()
+			h.Write([]byte(source.Contents))
+			hash = hashForFileName(h.Sum(nil))
 		}
 		dir := "/"
 		relPath := config.TemplateToString(config.SubstituteTemplate(args.options.AssetPathTemplate, config.PathPlaceholders{
@@ -967,8 +968,8 @@ func lowerCaseAbsPathForWindows(absPath string) string {
 	return strings.ToLower(absPath)
 }
 
-func hashForFileName(hashBytes [sha1.Size]byte) string {
-	return base32.StdEncoding.EncodeToString(hashBytes[:])[:8]
+func hashForFileName(hashBytes []byte) string {
+	return base32.StdEncoding.EncodeToString(hashBytes)[:8]
 }
 
 type scanner struct {

internal/bundler/linker.go

@@ -2,7 +2,6 @@ package bundler
 
 import (
 	"bytes"
-	"crypto/sha1"
 	"encoding/base64"
 	"encoding/binary"
 	"fmt"
@@ -28,6 +27,7 @@ import (
 	"github.com/evanw/esbuild/internal/resolver"
 	"github.com/evanw/esbuild/internal/runtime"
 	"github.com/evanw/esbuild/internal/sourcemap"
+	"github.com/evanw/esbuild/internal/xxhash"
 )
 
 type bitSet struct {
@@ -641,17 +641,17 @@ func (c *linkerContext) generateChunksInParallel(chunks []chunkInfo) []OutputFil
 	// parallel but it probably doesn't matter so much because we're not hashing
 	// that much data.
 	visited := make([]uint32, len(chunks))
-	var finalBytes [sha1.Size]byte
+	var finalBytes []byte
 	for chunkIndex := range chunks {
 		chunk := &chunks[chunkIndex]
 		var hashSubstitution *string
 
 		// Only wait for the hash if necessary
 		if config.HasPlaceholder(chunk.finalTemplate, config.HashPlaceholder) {
 			// Compute the final hash using the isolated hashes of the dependencies
-			hash := sha1.New()
+			hash := xxhash.New()
 			appendIsolatedHashesForImportedChunks(hash, chunks, uint32(chunkIndex), visited, ^uint32(chunkIndex))
-			hash.Sum(finalBytes[:0])
+			finalBytes = hash.Sum(finalBytes[:0])
 			finalString := hashForFileName(finalBytes)
 			hashSubstitution = &finalString
 		}
@@ -4909,7 +4909,7 @@ func (c *linkerContext) generateIsolatedHashInParallel(chunk *chunkInfo) {
 }
 
 func (c *linkerContext) generateIsolatedHash(chunk *chunkInfo, channel chan []byte) {
-	hash := sha1.New()
+	hash := xxhash.New()
 
 	// Mix the file names and part ranges of all of the files in this chunk into
 	// the hash. Objects that appear identical but that live in separate files or

internal/bundler/snapshots/snapshots_css.txt

@@ -18,20 +18,20 @@ TestCSSAndJavaScriptCodeSplittingIssue1064
 ---------- /out/a.js ----------
 import {
   shared_default
-} from "./chunk-JWQFE3AN.js";
+} from "./chunk-JHSNRTG6.js";
 
 // a.js
 console.log(shared_default() + 1);
 
 ---------- /out/b.js ----------
 import {
   shared_default
-} from "./chunk-JWQFE3AN.js";
+} from "./chunk-JHSNRTG6.js";
 
 // b.js
 console.log(shared_default() + 2);
 
----------- /out/chunk-JWQFE3AN.js ----------
+---------- /out/chunk-JHSNRTG6.js ----------
 // shared.js
 function shared_default() {
   return 3;
@@ -53,7 +53,7 @@ body {
   color: blue;
 }
 
----------- /out/chunk-Y6KZESIP.css ----------
+---------- /out/chunk-C7T4PGKL.css ----------
 /* shared.css */
 body {
   background: black;
@@ -183,17 +183,17 @@ path {
 
 ================================================================================
 TestFileImportURLInCSS
----------- /out/example-RPS4CMHF.data ----------
+---------- /out/example-GDKWWYFY.data ----------
 This is some data.
 ---------- /out/entry.css ----------
 /* one.css */
 a {
-  background: url(./example-RPS4CMHF.data);
+  background: url(./example-GDKWWYFY.data);
 }
 
 /* two.css */
 b {
-  background: url(./example-RPS4CMHF.data);
+  background: url(./example-GDKWWYFY.data);
 }
 
 /* entry.css */

internal/bundler/snapshots/snapshots_default.txt

@@ -1320,14 +1320,14 @@ console.log(a, b);
 
 ================================================================================
 TestLoaderFileWithQueryParameter
----------- /out/file-JAWLBT6L.txt ----------
+---------- /out/file-UEHVHXRQ.txt ----------
 This is some text
 ---------- /out/entry.js ----------
 // file.txt?foo
-var file_default = "./file-JAWLBT6L.txt?foo";
+var file_default = "./file-UEHVHXRQ.txt?foo";
 
 // file.txt?bar
-var file_default2 = "./file-JAWLBT6L.txt?bar";
+var file_default2 = "./file-UEHVHXRQ.txt?bar";
 
 // entry.js
 console.log(file_default, file_default2);
@@ -2650,26 +2650,26 @@ var import_es6_ns_export_abstract_class = __toModule(require_es6_ns_export_abstr
 TestTopLevelAwaitAllowedImportWithSplitting
 ---------- /out/entry.js ----------
 // entry.js
-import("./a-4AEJWCHS.js");
-import("./b-6EB7BLIM.js");
-import("./c-VSFX3WL4.js");
+import("./a-ZK7H2YZU.js");
+import("./b-MPIVDXIR.js");
+import("./c-F7O26T5D.js");
 require_entry();
 await 0;
 
----------- /out/a-4AEJWCHS.js ----------
-import "./chunk-K5FAGUED.js";
-import "./chunk-7Y4CCLAO.js";
+---------- /out/a-ZK7H2YZU.js ----------
+import "./chunk-BYXBJQAS.js";
+import "./chunk-34XDKUTO.js";
 
----------- /out/b-6EB7BLIM.js ----------
-import "./chunk-K5FAGUED.js";
-import "./chunk-7Y4CCLAO.js";
+---------- /out/b-MPIVDXIR.js ----------
+import "./chunk-BYXBJQAS.js";
+import "./chunk-34XDKUTO.js";
 
----------- /out/chunk-K5FAGUED.js ----------
+---------- /out/chunk-BYXBJQAS.js ----------
 
----------- /out/c-VSFX3WL4.js ----------
-import "./chunk-7Y4CCLAO.js";
+---------- /out/c-F7O26T5D.js ----------
+import "./chunk-34XDKUTO.js";
 
----------- /out/chunk-7Y4CCLAO.js ----------
+---------- /out/chunk-34XDKUTO.js ----------
 // c.js
 await 0;
 

internal/bundler/snapshots/snapshots_loader.txt

@@ -46,49 +46,49 @@ console.log(x_url, y_default);
 
 ================================================================================
 TestLoaderFile
----------- /out/test-T3K5TRK4.svg ----------
+---------- /out/test-IPILGNO5.svg ----------
 <svg></svg>
 ---------- /out/entry.js ----------
 // test.svg
 var require_test = __commonJS((exports, module) => {
-  module.exports = "./test-T3K5TRK4.svg";
+  module.exports = "./test-IPILGNO5.svg";
 });
 
 // entry.js
 console.log(require_test());
 
 ================================================================================
 TestLoaderFileCommonJSAndES6
----------- /y-SXFQX7JJ.txt ----------
+---------- /y-YE5AYNFB.txt ----------
 y
----------- /x-CH3K3DWF.txt ----------
+---------- /x-LSAMBFUD.txt ----------
 x
 ---------- /out.js ----------
 // x.txt
 var require_x = __commonJS((exports, module) => {
-  module.exports = "./x-CH3K3DWF.txt";
+  module.exports = "./x-LSAMBFUD.txt";
 });
 
 // y.txt
-var y_default = "./y-SXFQX7JJ.txt";
+var y_default = "./y-YE5AYNFB.txt";
 
 // entry.js
 var x_url = require_x();
 console.log(x_url, y_default);
 
 ================================================================================
 TestLoaderFileMultipleNoCollision
----------- /dist/test-VFFI7ZOM.txt ----------
+---------- /dist/test-J7OMUXO3.txt ----------
 test
 ---------- /dist/out.js ----------
 // a/test.txt
 var require_test = __commonJS((exports, module) => {
-  module.exports = "./test-VFFI7ZOM.txt";
+  module.exports = "./test-J7OMUXO3.txt";
 });
 
 // b/test.txt
 var require_test2 = __commonJS((exports, module) => {
-  module.exports = "./test-VFFI7ZOM.txt";
+  module.exports = "./test-J7OMUXO3.txt";
 });
 
 // entry.js