Fix v3 prebuild naming for Rust builds (#100)

* Fix v3 prebuild naming for Rust builds

PR #90 refactored prebuild output naming into a shared
prebuildFilename() function, but the v3 code path hardcoded the
"node-{abi}.node" prefix, ignoring the baseName parameter. This broke
Rust builds which previously preserved the original binary name from
build/Release/ (e.g. "process-discovery-napi.node" became
"node-napi.node"), causing consumers like libdatadog-nodejs to fail
with "Could not find a {name} binary for {platform}".

The fix makes prebuildFilename() use baseName in the v3 path, and
passes 'node' from the non-Rust call site to preserve backward
compatibility there.

Test have also been added to cover the functionality.

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: szegedi

package.json

@@ -11,7 +11,7 @@
     "rebuild": "node-gyp rebuild",
     "prebuild": "node prebuild",
     "lint": "eslint .",
-    "test": "node test"
+    "test": "node test/naming && node test"
   },
   "dependencies": {
     "node-gyp-build": "^3.9.0"

prebuild/index.js

@@ -6,6 +6,7 @@ const fs = require('fs')
 const execSync = require('child_process').execSync
 const semver = require('semver')
 const { getFilteredNodeTargets } = require('./targets')
+const naming = require('./naming')
 
 const platform = os.platform()
 const arch = process.env.ARCH || os.arch()
@@ -28,35 +29,12 @@ const {
   NODE_GYP_BUILD_MAJOR = '3'
 } = process.env
 
-// Prebuild directory and filename conventions differ between node-gyp-build v3 and v4:
-//
-// v3: prebuilds/${platform}${libc}-${arch}/node-${abi}.node
-//     e.g. prebuilds/linuxglibc-arm64/node-115.node
-//
-// v4: prebuilds/${platform}-${arch}/${TARGET_NAME}[.musl].node.[napi|abi${N}].node
-//     e.g. prebuilds/linux-arm64/dd_pprof.node.abi115.node
-//          prebuilds/linux-arm64/dd_pprof.musl.node.napi.node
-//
-// When NODE_GYP_BUILD_MAJOR=4, libc is encoded as a filename tag ('musl' only;
-// glibc is the default and needs no tag) rather than in the directory name.
-
 function prebuildDir () {
-  if (NODE_GYP_BUILD_MAJOR === '4') {
-    return `${DIRECTORY_PATH}/prebuilds/${platform}-${arch}`
-  }
-  return `${DIRECTORY_PATH}/prebuilds/${platform}${libc}-${arch}`
+  return naming.prebuildDir(NODE_GYP_BUILD_MAJOR, DIRECTORY_PATH, platform, arch, libc)
 }
 
 function prebuildFilename (abi, baseName) {
-  if (NODE_GYP_BUILD_MAJOR === '4') {
-    const libcTag = libc === 'musl' ? '.musl' : ''
-    const abiTag = abi === 'napi' ? '.napi' : `.abi${abi}`
-    return `${baseName}${libcTag}.node${abiTag}.node`
-  }
-  if (abi === 'napi') {
-    return 'node-napi.node'
-  }
-  return `node-${abi}.node`
+  return naming.prebuildFilename(NODE_GYP_BUILD_MAJOR, abi, baseName, libc)
 }
 
 let alpineVersion
@@ -162,7 +140,8 @@ function prebuildTarget (arch, target) {
       fs.copyFileSync(`${DIRECTORY_PATH}/build/Release/${name}`, output)
     }
   } else {
-    const output = `${prebuildDir()}/${prebuildFilename(target.abi, TARGET_NAME)}`
+    const baseName = NODE_GYP_BUILD_MAJOR === '4' ? TARGET_NAME : 'node'
+    const output = `${prebuildDir()}/${prebuildFilename(target.abi, baseName)}`
     const input = NAPI_RS === 'true'
       ? `${DIRECTORY_PATH}/${TARGET_NAME}.node`
       : `${DIRECTORY_PATH}/build/Release/${TARGET_NAME}.node`

prebuild/naming.js

@@ -0,0 +1,35 @@
+'use strict'
+
+// Prebuild directory and filename conventions differ between node-gyp-build v3 and v4:
+//
+// v3: prebuilds/${platform}${libc}-${arch}/${baseName}-${abi}.node
+//     e.g. prebuilds/linuxglibc-arm64/node-115.node
+//          prebuilds/linuxmusl-x64/process-discovery-napi.node
+//
+// v4: prebuilds/${platform}-${arch}/${baseName}[.musl].node.[napi|abi${N}].node
+//     e.g. prebuilds/linux-arm64/dd_pprof.node.abi115.node
+//          prebuilds/linux-arm64/dd_pprof.musl.node.napi.node
+//
+// When nodeGypBuildMajor=4, libc is encoded as a filename tag ('musl' only;
+// glibc is the default and needs no tag) rather than in the directory name.
+
+function prebuildDir (nodeGypBuildMajor, directoryPath, platform, arch, libc) {
+  if (nodeGypBuildMajor === '4') {
+    return `${directoryPath}/prebuilds/${platform}-${arch}`
+  }
+  return `${directoryPath}/prebuilds/${platform}${libc}-${arch}`
+}
+
+function prebuildFilename (nodeGypBuildMajor, abi, baseName, libc) {
+  if (nodeGypBuildMajor === '4') {
+    const libcTag = libc === 'musl' ? '.musl' : ''
+    const abiTag = abi === 'napi' ? '.napi' : `.abi${abi}`
+    return `${baseName}${libcTag}.node${abiTag}.node`
+  }
+  if (abi === 'napi') {
+    return `${baseName}-napi.node`
+  }
+  return `${baseName}-${abi}.node`
+}
+
+module.exports = { prebuildDir, prebuildFilename }

test/naming.js

@@ -0,0 +1,39 @@
+'use strict'
+
+const { strictEqual } = require('assert')
+const { prebuildDir, prebuildFilename } = require('../prebuild/naming')
+
+// --- prebuildDir ---
+
+// v3: directory encodes libc
+strictEqual(prebuildDir('3', '.', 'linux', 'x64', 'glibc'), './prebuilds/linuxglibc-x64')
+strictEqual(prebuildDir('3', '.', 'linux', 'x64', 'musl'), './prebuilds/linuxmusl-x64')
+strictEqual(prebuildDir('3', '.', 'linux', 'arm64', 'glibc'), './prebuilds/linuxglibc-arm64')
+strictEqual(prebuildDir('3', '.', 'darwin', 'arm64', ''), './prebuilds/darwin-arm64')
+
+// v4: no libc in directory
+strictEqual(prebuildDir('4', '.', 'linux', 'x64', 'glibc'), './prebuilds/linux-x64')
+strictEqual(prebuildDir('4', '.', 'linux', 'x64', 'musl'), './prebuilds/linux-x64')
+strictEqual(prebuildDir('4', '.', 'darwin', 'arm64', ''), './prebuilds/darwin-arm64')
+
+// --- prebuildFilename ---
+
+// v3 non-Rust (baseName='node'): traditional node-gyp-build convention
+strictEqual(prebuildFilename('3', 'napi', 'node', ''), 'node-napi.node')
+strictEqual(prebuildFilename('3', '115', 'node', ''), 'node-115.node')
+strictEqual(prebuildFilename('3', '127', 'node', 'musl'), 'node-127.node')
+
+// v3 Rust (baseName from build output): preserves original binary name
+strictEqual(prebuildFilename('3', 'napi', 'process-discovery', ''), 'process-discovery-napi.node')
+strictEqual(prebuildFilename('3', 'napi', 'process-discovery', 'musl'), 'process-discovery-napi.node')
+strictEqual(prebuildFilename('3', 'napi', 'crashtracker', ''), 'crashtracker-napi.node')
+
+// v4 non-Rust (baseName=TARGET_NAME): uses target name with libc tag
+strictEqual(prebuildFilename('4', 'napi', 'addon', ''), 'addon.node.napi.node')
+strictEqual(prebuildFilename('4', '115', 'addon', ''), 'addon.node.abi115.node')
+strictEqual(prebuildFilename('4', 'napi', 'addon', 'musl'), 'addon.musl.node.napi.node')
+strictEqual(prebuildFilename('4', '115', 'addon', 'musl'), 'addon.musl.node.abi115.node')
+
+// v4 Rust (baseName from build output): uses original name with libc tag
+strictEqual(prebuildFilename('4', 'napi', 'dd_pprof', ''), 'dd_pprof.node.napi.node')
+strictEqual(prebuildFilename('4', 'napi', 'dd_pprof', 'musl'), 'dd_pprof.musl.node.napi.node')