feat: add Erlang problem matchers (#433)

* feat: add Erlang problem matchers for erlc, dialyzer, CT, and EUnit

Adds GitHub Actions problem matchers for Erlang tooling, matching the
existing Elixir matcher support. Covers erlc errors/warnings (which
also catches dialyzer output), Common Test failures, and EUnit failures.

Closes #390

* chore: rebuild dist bundle and format test file

* refactor: move Erlang matchers into installOTP function

Moves maybeEnableErlangProblemMatchers() call inside installOTP(),
between setOutput and endGroup, matching the Elixir pattern.

* refactor: extract generic maybeEnableProblemMatchers function

Replaces separate maybeEnableErlangProblemMatchers and
maybeEnableElixirProblemMatchers with a single generic
maybeEnableProblemMatchers(language) and a problemMatchersEnabled()
helper.

* fix: use static paths for ncc to resolve matcher JSON files

ncc cannot trace dynamic template literals, so the matcher JSON files
were not being copied to dist/. Use a static map of paths instead.

dist/erlang-matchers.json

@@ -0,0 +1,66 @@
+{
+  "problemMatcher": [
+    {
+      "owner": "erlc-warning",
+      "severity": "warning",
+      "pattern": [
+        {
+          "regexp": "^(\\S+):(\\d+):(\\d+): [wW]arning: (.+)$",
+          "file": 1,
+          "line": 2,
+          "column": 3,
+          "message": 4
+        }
+      ]
+    },
+    {
+      "owner": "erlc-error",
+      "severity": "error",
+      "pattern": [
+        {
+          "regexp": "^(\\S+):(\\d+):(\\d+): (?![wW]arning)(.+)$",
+          "file": 1,
+          "line": 2,
+          "column": 3,
+          "message": 4
+        }
+      ]
+    },
+    {
+      "owner": "ct-failure",
+      "severity": "error",
+      "pattern": [
+        {
+          "regexp": "^(\\S+) failed on line (\\d+)$",
+          "file": 1,
+          "line": 2
+        },
+        {
+          "regexp": "^Reason: (.+)$",
+          "message": 1
+        }
+      ]
+    },
+    {
+      "owner": "eunit-failure",
+      "severity": "error",
+      "pattern": [
+        {
+          "regexp": "^\\S+: .+\\.\\.\\.\\*failed\\*$"
+        },
+        {
+          "regexp": "^in function .+ \\((.+), line (\\d+)\\)$",
+          "file": 1,
+          "line": 2
+        },
+        {
+          "regexp": "^in call from .+$"
+        },
+        {
+          "regexp": "^\\*\\*error:(.+)$",
+          "message": 1
+        }
+      ]
+    }
+  ]
+}

dist/index.js

@@ -57588,6 +57588,7 @@ async function installOTP(otpSpec) {
     },
   })
   setOutput('otp-version', otpVersion)
+  maybeEnableProblemMatchers('erlang')
   endGroup()
 
   return otpVersion
@@ -57609,7 +57610,7 @@ async function maybeInstallElixir(elixirSpec) {
       },
     })
     setOutput('elixir-version', elixirVersion)
-    maybeEnableElixirProblemMatchers()
+    maybeEnableProblemMatchers('elixir')
     endGroup()
 
     installed = true
@@ -57618,14 +57619,18 @@ async function maybeInstallElixir(elixirSpec) {
   return installed
 }
 
-function maybeEnableElixirProblemMatchers() {
-  const disableProblemMatchers = setup_beam_getInput('disable_problem_matchers', false)
-  if (disableProblemMatchers === 'false') {
-    // path.join helps ncc figure this out
-    const elixirMatchers = external_node_path_namespaceObject.join(
-      __nccwpck_require__.ab + "elixir-matchers.json",
-    )
-    info(`##[add-matcher]${elixirMatchers}`)
+function problemMatchersEnabled() {
+  return setup_beam_getInput('disable_problem_matchers', false) === 'false'
+}
+
+// path.join with static strings helps ncc resolve and bundle the JSON files
+function maybeEnableProblemMatchers(language) {
+  if (problemMatchersEnabled()) {
+    const matcherFiles = {
+      erlang: external_node_path_namespaceObject.join(__nccwpck_require__.ab + "erlang-matchers.json"),
+      elixir: external_node_path_namespaceObject.join(__nccwpck_require__.ab + "elixir-matchers.json"),
+    }
+    info(`##[add-matcher]${matcherFiles[language]}`)
   }
 }
 

matchers/erlang-matchers.json

@@ -0,0 +1,66 @@
+{
+  "problemMatcher": [
+    {
+      "owner": "erlc-warning",
+      "severity": "warning",
+      "pattern": [
+        {
+          "regexp": "^(\\S+):(\\d+):(\\d+): [wW]arning: (.+)$",
+          "file": 1,
+          "line": 2,
+          "column": 3,
+          "message": 4
+        }
+      ]
+    },
+    {
+      "owner": "erlc-error",
+      "severity": "error",
+      "pattern": [
+        {
+          "regexp": "^(\\S+):(\\d+):(\\d+): (?![wW]arning)(.+)$",
+          "file": 1,
+          "line": 2,
+          "column": 3,
+          "message": 4
+        }
+      ]
+    },
+    {
+      "owner": "ct-failure",
+      "severity": "error",
+      "pattern": [
+        {
+          "regexp": "^(\\S+) failed on line (\\d+)$",
+          "file": 1,
+          "line": 2
+        },
+        {
+          "regexp": "^Reason: (.+)$",
+          "message": 1
+        }
+      ]
+    },
+    {
+      "owner": "eunit-failure",
+      "severity": "error",
+      "pattern": [
+        {
+          "regexp": "^\\S+: .+\\.\\.\\.\\*failed\\*$"
+        },
+        {
+          "regexp": "^in function .+ \\((.+), line (\\d+)\\)$",
+          "file": 1,
+          "line": 2
+        },
+        {
+          "regexp": "^in call from .+$"
+        },
+        {
+          "regexp": "^\\*\\*error:(.+)$",
+          "message": 1
+        }
+      ]
+    }
+  ]
+}

src/setup-beam.js

@@ -80,6 +80,7 @@ async function installOTP(otpSpec) {
     },
   })
   core.setOutput('otp-version', otpVersion)
+  maybeEnableProblemMatchers('erlang')
   core.endGroup()
 
   return otpVersion
@@ -101,7 +102,7 @@ async function maybeInstallElixir(elixirSpec) {
       },
     })
     core.setOutput('elixir-version', elixirVersion)
-    maybeEnableElixirProblemMatchers()
+    maybeEnableProblemMatchers('elixir')
     core.endGroup()
 
     installed = true
@@ -110,14 +111,18 @@ async function maybeInstallElixir(elixirSpec) {
   return installed
 }
 
-function maybeEnableElixirProblemMatchers() {
-  const disableProblemMatchers = getInput('disable_problem_matchers', false)
-  if (disableProblemMatchers === 'false') {
-    // path.join helps ncc figure this out
-    const elixirMatchers = path.join(
-      `${__dirname}/../matchers/elixir-matchers.json`,
-    )
-    core.info(`##[add-matcher]${elixirMatchers}`)
+function problemMatchersEnabled() {
+  return getInput('disable_problem_matchers', false) === 'false'
+}
+
+// path.join with static strings helps ncc resolve and bundle the JSON files
+function maybeEnableProblemMatchers(language) {
+  if (problemMatchersEnabled()) {
+    const matcherFiles = {
+      erlang: path.join(`${__dirname}/../matchers/erlang-matchers.json`),
+      elixir: path.join(`${__dirname}/../matchers/elixir-matchers.json`),
+    }
+    core.info(`##[add-matcher]${matcherFiles[language]}`)
   }
 }
 

test/setup-beam.test.js

@@ -6,7 +6,9 @@ import path from 'node:path'
 import { describe, it } from 'node:test'
 import * as csv from 'csv-parse/sync'
 import elixirMatchers from '../matchers/elixir-matchers.json' with { type: 'json' }
+import erlangMatchers from '../matchers/erlang-matchers.json' with { type: 'json' }
 const { problemMatcher } = elixirMatchers
+const { problemMatcher: erlangProblemMatcher } = erlangMatchers
 
 process.env.NODE_ENV = 'test'
 
@@ -1159,6 +1161,98 @@ describe("Elixir Mix matcher's", () => {
   })
 })
 
+describe("Erlang matcher's", () => {
+  it('erlc errors are properly matched', () => {
+    const [matcher] = erlangProblemMatcher.find(
+      ({ owner }) => owner === 'erlc-error',
+    ).pattern
+
+    const output = 'src/mymod.erl:42:5: head mismatch'
+    const match = output.match(matcher.regexp)
+    assert.equal(match[1], 'src/mymod.erl')
+    assert.equal(match[2], '42')
+    assert.equal(match[3], '5')
+    assert.equal(match[4], 'head mismatch')
+  })
+
+  it('erlc errors do not match warnings', () => {
+    const [matcher] = erlangProblemMatcher.find(
+      ({ owner }) => owner === 'erlc-error',
+    ).pattern
+
+    const output = 'src/mymod.erl:42:5: Warning: variable X is unused'
+    const match = output.match(matcher.regexp)
+    assert.equal(match, null)
+  })
+
+  it('erlc warnings are properly matched', () => {
+    const [matcher] = erlangProblemMatcher.find(
+      ({ owner }) => owner === 'erlc-warning',
+    ).pattern
+
+    const output = 'src/mymod.erl:10:3: Warning: variable X is unused'
+    const match = output.match(matcher.regexp)
+    assert.equal(match[1], 'src/mymod.erl')
+    assert.equal(match[2], '10')
+    assert.equal(match[3], '3')
+    assert.equal(match[4], 'variable X is unused')
+  })
+
+  it('dialyzer warnings are matched via erlc patterns', () => {
+    const [matcher] = erlangProblemMatcher.find(
+      ({ owner }) => owner === 'erlc-warning',
+    ).pattern
+
+    const output =
+      'src/mymod.erl:25:1: warning: Function foo/0 has no local return'
+    const match = output.match(matcher.regexp)
+    assert.equal(match[1], 'src/mymod.erl')
+    assert.equal(match[2], '25')
+    assert.equal(match[3], '1')
+    assert.equal(match[4], 'Function foo/0 has no local return')
+  })
+
+  it('CT failures are properly matched', () => {
+    const [filePattern, reasonPattern] = erlangProblemMatcher.find(
+      ({ owner }) => owner === 'ct-failure',
+    ).pattern
+
+    const firstOutput = 'test/mymod_SUITE.erl failed on line 55'
+    const secondOutput = 'Reason: {badmatch,{error,timeout}}'
+
+    const fileMatch = firstOutput.match(filePattern.regexp)
+    assert.equal(fileMatch[1], 'test/mymod_SUITE.erl')
+    assert.equal(fileMatch[2], '55')
+
+    const reasonMatch = secondOutput.match(reasonPattern.regexp)
+    assert.equal(reasonMatch[1], '{badmatch,{error,timeout}}')
+  })
+
+  it('EUnit failures are properly matched', () => {
+    const [headerPattern, funcPattern, callPattern, errorPattern] =
+      erlangProblemMatcher.find(
+        ({ owner }) => owner === 'eunit-failure',
+      ).pattern
+
+    const header = 'mymod_test: hello_test....*failed*'
+    const func =
+      'in function mymod_test:hello_test/0 (test/mymod_test.erl, line 12)'
+    const call = 'in call from mymod_test:hello_test/0'
+    const error = '**error:{badmatch,false}'
+
+    assert.ok(header.match(headerPattern.regexp))
+
+    const funcMatch = func.match(funcPattern.regexp)
+    assert.equal(funcMatch[1], 'test/mymod_test.erl')
+    assert.equal(funcMatch[2], '12')
+
+    assert.ok(call.match(callPattern.regexp))
+
+    const errorMatch = error.match(errorPattern.regexp)
+    assert.equal(errorMatch[1], '{badmatch,false}')
+  })
+})
+
 function unsimulateInput(key) {
   return simulateInput(key, '')
 }