[JS/TS] Allows compiling fable-library-ts for Browser environment

src/Fable.Cli/CHANGELOG.md

@@ -21,6 +21,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 * [Beam] Fix generic constraint interface dispatch (by @dbrattli)
 * [Beam] Fix class constructor field invokes and explicit val fields (by @dbrattli)
 * [Beam] Fix mutable record field mutation (by @dbrattli)
+* [JS/TS] Allows compiling `fable-library-ts` for Browser environment (by @goswinr)
 
 ## 5.0.0-rc.1 - 2026-02-26
 

src/fable-library-ts/CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+### Fixed
+
+* [JS/TS] Allows compiling `fable-library-ts` for Browser environment (by @goswinr)
+
 ## 2.0.0-rc.1 - 2026-02-26
 
 ## 2.0.0-beta.7 - 2026-02-03

src/fable-library-ts/Encoding.ts

@@ -98,8 +98,11 @@ class UTF16LE {
     } else if (index != null) {
       str = str.substring(index);
     }
-    if (typeof Buffer !== "undefined") {
-      const bytes = Buffer.from(str, "utf16le");
+    // Allow to compile for Browser environment without @types/node being installed
+    // See https://github.com/fable-compiler/Fable/issues/4368
+    const g = globalThis as any;
+    if (typeof g.Buffer !== "undefined") {
+      const bytes = g.Buffer.from(str, "utf16le");
       return new Uint8Array(bytes.buffer, bytes.byteOffset, bytes.byteLength);
     } else {
       return utf16le_encode(str); // polyfill
@@ -114,10 +117,13 @@ class UTF16LE {
     } else if (index != null) {
       buffer = buffer.subarray(index);
     }
+    // Allow to compile for Browser environment without @types/node being installed
+    // See https://github.com/fable-compiler/Fable/issues/4368
+    const g = globalThis as any;
     if (typeof TextDecoder !== "undefined") {
       return new TextDecoder("utf-16le").decode(buffer);
-    } else if (typeof Buffer !== "undefined") {
-      return Buffer.from(buffer).toString("utf16le");
+    } else if (typeof g.Buffer !== "undefined") {
+      return g.Buffer.from(buffer).toString("utf16le");
     } else {
       return utf16le_decode(buffer); // polyfill
     }
@@ -134,10 +140,13 @@ class UTF8 {
     } else if (index != null) {
       str = str.substring(index);
     }
+    // Allow to compile for Browser environment without @types/node being installed
+    // See https://github.com/fable-compiler/Fable/issues/4368
+    const g = globalThis as any;
     if (typeof TextEncoder !== "undefined") {
       return new TextEncoder().encode(str);
-    } else if (typeof Buffer !== "undefined") {
-      const bytes = Buffer.from(str, "utf8");
+    } else if (typeof g.Buffer !== "undefined") {
+      const bytes = g.Buffer.from(str, "utf8");
       return new Uint8Array(bytes.buffer, bytes.byteOffset, bytes.byteLength);
     } else {
       return utf8_encode(str); // polyfill
@@ -152,10 +161,13 @@ class UTF8 {
     } else if (index != null) {
       buffer = buffer.subarray(index);
     }
+    // Allow to compile for Browser environment without @types/node being installed
+    // See https://github.com/fable-compiler/Fable/issues/4368
+    const g = globalThis as any;
     if (typeof TextDecoder !== "undefined") {
       return new TextDecoder().decode(buffer);
-    } else if (typeof Buffer !== "undefined") {
-      return Buffer.from(buffer).toString("utf8");
+    } else if (typeof g.Buffer !== "undefined") {
+      return g.Buffer.from(buffer).toString("utf8");
     } else {
       return utf8_decode(buffer); // polyfill
     }