feat(jsruntime): Response/Request/Headers Web Fetch API globals in V8 fallback#1016
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… fallback The next hono blocker after the SIGSEGV fix (v0.5.1005) was `ReferenceError: Response is not defined` thrown from `node_modules/hono/dist/context.js`. deno_core does not expose Response/Request as globals, and the existing Headers polyfill was nested inside an `if (typeof fetch === 'undefined')` branch that was skipped on V8 builds (which already have their own fetch). Hoists Headers out of the fetch guard (now unconditional) and adds polyfills for Response and Request implementing the minimal Web Fetch API surface hono needs: status/statusText/headers/ok, text()/json()/ arrayBuffer(), clone(), Response.error()/redirect()/json() statics, Request shape fields, generator-style Headers iteration. Hono /tmp/perry-compat-sweep/hono now completes the full round-trip (app.fetch(req) -> res.text() -> 'pong') matching expected.txt.
This was referenced May 18, 2026
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Summary
Headerspolyfill out of theif (typeof fetch === 'undefined')guard so it is created unconditionally — deno_core has its ownfetchbut does not exposeHeaders, leaving hono'snew Headers()calls incontext.jsto throwReferenceError.ResponseandRequestpolyfills implementing the minimal Web Fetch API surface (status/statusText/headers/ok/body,text()/json()/arrayBuffer()/clone(), staticResponse.error/redirect/json, fullRequestshape fields).Headersgainsappend(), copy-construction, generator-style iteration, andSymbol.toStringTag.fetch()polyfill to return a realResponseinstance instead of an ad-hoc object literal, and to accept a passed-inRequestasinput.Test plan
cargo build --release -p perry-runtime -p perry-stdlib -p perry-jsruntime -p perrytest-files/test_v8_response_request.ts(native path throughperry-stdlib::fetch) prints200 / hello / http://example.com/ / POST / text/plain/tmp/perry-compat-sweep/hono/entry.tsrebuilt with--enable-js-runtime: previously threwReferenceError: Response is not defined, now completesapp.fetch(new Request(...))round-trip and printsbody=pongmatchingexpected.txt