Add Gleam (#67)

.github/workflows/ubuntu.yml

@@ -14,6 +14,7 @@ jobs:
     name: >
       OTP ${{matrix.combo.otp-version}},
       Elixir ${{matrix.combo.elixir-version}},
+      Gleam ${{matrix.combo.gleam-version}},
       rebar3 ${{matrix.combo.rebar3-version}}
     runs-on: ${{matrix.combo.os}}
     strategy:
@@ -106,6 +107,10 @@ jobs:
           - elixir-version: 'master'
             otp-version: '23.1'
             os:  'ubuntu-20.04'
+          - gleam-version: '0.16'
+            otp-version: '24'
+            rebar3-version: '3.16'
+            os: 'ubuntu-latest'
     steps:
       - uses: actions/checkout@v2
       - name: Use erlef/setup-beam
@@ -114,6 +119,7 @@ jobs:
         with:
           otp-version: ${{matrix.combo.otp-version}}
           elixir-version: ${{matrix.combo.elixir-version}}
+          gleam-version: ${{matrix.combo.gleam-version}}
           rebar3-version: ${{matrix.combo.rebar3-version}}
           version-type: ${{matrix.combo.version-type}}
       - name: Erlang/OTP version (action)
@@ -121,6 +127,9 @@ jobs:
       - name: Elixir version (action)
         run: echo "Elixir ${{steps.setup-beam.outputs.elixir-version}}"
         if: ${{matrix.combo.elixir-version}}
+      - name: Gleam version (action)
+        run: echo "Gleam ${{steps.setup-beam.outputs.gleam-version}}"
+        if: ${{matrix.combo.gleam-version}}
       - name: rebar3 version (action)
         run: echo "rebar3 ${{steps.setup-beam.outputs.rebar3-version}}"
         if: ${{matrix.combo.rebar3-version}}
@@ -130,14 +139,19 @@ jobs:
           mix help local.rebar
           mix help local.hex
         if: ${{matrix.combo.elixir-version}}
-      - name: Run Mix project tests
+      - name: Run Elixir/Mix project tests
         run: |
-          cd test-projects/mix
+          cd test-projects/elixir_mix
           mix deps.get
           mix test
         if: ${{matrix.combo.elixir-version}}
-      - name: Run rebar3 project tests
+      - name: Run Erlang/rebar3 project tests
         run: |
-          cd test-projects/rebar3
+          cd test-projects/erlang_rebar3
           rebar3 ct
         if: ${{matrix.combo.rebar3-version}}
+      - name: Run Gleam/rebar3 project tests
+        run: |
+          cd test-projects/gleam_rebar3
+          rebar3 eunit
+        if: ${{matrix.combo.gleam-version}}

.github/workflows/windows.yml

@@ -14,6 +14,7 @@ jobs:
     name: >
       OTP ${{matrix.combo.otp-version}},
       Elixir ${{matrix.combo.elixir-version}},
+      Gleam ${{matrix.combo.gleam-version}},
       rebar3 ${{matrix.combo.rebar3-version}}
     runs-on: ${{matrix.combo.os}}
     strategy:
@@ -52,6 +53,10 @@ jobs:
             otp-version: '24'
             rebar3-version: '3.15'
             os: 'windows-latest'
+          - gleam-version: '0.16'
+            otp-version: '24'
+            rebar3-version: '3.16'
+            os: 'windows-latest'
     steps:
       - uses: actions/checkout@v2
       - name: Use erlef/setup-beam
@@ -60,12 +65,16 @@ jobs:
         with:
           otp-version: ${{matrix.combo.otp-version}}
           elixir-version: ${{matrix.combo.elixir-version}}
+          gleam-version: ${{matrix.combo.gleam-version}}
           rebar3-version: ${{matrix.combo.rebar3-version}}
       - name: Erlang/OTP version (action)
         run: echo "Erlang/OTP ${{steps.setup-beam.outputs.otp-version}}"
       - name: Elixir version (action)
         run: echo "Elixir ${{steps.setup-beam.outputs.elixir-version}}"
         if: ${{matrix.combo.elixir-version}}
+      - name: Gleam version (action)
+        run: echo "Gleam ${{steps.setup-beam.outputs.gleam-version}}"
+        if: ${{matrix.combo.gleam-version}}
       - name: rebar3 version (action)
         run: echo "rebar3 ${{steps.setup-beam.outputs.rebar3-version}}"
       - name: mix version and help (CLI)
@@ -74,14 +83,19 @@ jobs:
           mix help local.rebar
           mix help local.hex
         if: ${{matrix.combo.elixir-version}}
-      - name: Run Mix project tests
+      - name: Run Elixir/Mix project tests
         run: |
-          cd test-projects/mix
+          cd test-projects/elixir_mix
           mix deps.get
           mix test
         if: ${{matrix.combo.elixir-version}}
-      - name: Run rebar3 project tests
+      - name: Run Erlang/rebar3 project tests
         run: |
-          cd test-projects/rebar3
+          cd test-projects/erlang_rebar3
           rebar3 ct
         if: ${{matrix.combo.rebar3-version}}
+      - name: Run Gleam/rebar3 project tests
+        run: |
+          cd test-projects/gleam_rebar3
+          rebar3 eunit
+        if: ${{matrix.combo.gleam-version}}

3RD_PARTY_LICENSES

@@ -1810,7 +1810,7 @@ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLI
 
 -----
 
-The following software may be included in this product: has-bigints, unbox-primitive, which-boxed-primitive. A copy of the source code may be downloaded from git+https://github.com/ljharb/has-bigints.git (has-bigints), git+https://github.com/ljharb/unbox-primitive.git (unbox-primitive), git+https://github.com/inspect-js/which-boxed-primitive.git (which-boxed-primitive). This software contains the following license and notice below:
+The following software may be included in this product: has-bigints, internal-slot, side-channel, unbox-primitive, which-boxed-primitive. A copy of the source code may be downloaded from git+https://github.com/ljharb/has-bigints.git (has-bigints), git+https://github.com/ljharb/internal-slot.git (internal-slot), git+https://github.com/ljharb/side-channel.git (side-channel), git+https://github.com/ljharb/unbox-primitive.git (unbox-primitive), git+https://github.com/inspect-js/which-boxed-primitive.git (which-boxed-primitive). This software contains the following license and notice below:
 
 MIT License
 

README.md

@@ -13,6 +13,7 @@ workflow by:
 
 - installing Erlang/OTP
 - optionally, installing Elixir
+- optionally, installing Gleam
 - optionally, installing `rebar3`
 - optionally, installing `hex`
 
@@ -24,13 +25,13 @@ See [action.yml](action.yml) for the action's specification.
 
 **Note**: The Erlang/OTP release version specification is [relatively
 complex](http://erlang.org/doc/system_principles/versions.html#version-scheme).
-For best results, we recommend specifying exact Erlang/OTP, Elixir versions, and
+For best results, we recommend specifying exact
-`rebar3` versions, and setting option `version-type` to `strict`.
+versions, and setting option `version-type` to `strict`.
 However, values like `22.x`, or even `>22`, are also accepted, and we attempt to resolve them
 according to semantic versioning rules. This implicitly means `version-type` is `loose`,
 which is also the default value for this option.
 
-Additionally, it is recommended that one specifies Erlang/OTP, Elixir and `rebar3` versions
+Additionally, it is recommended that one specifies versions
 using YAML strings, as these examples do, so that numbers like `23.0` don't
 end up being parsed as `23`, which is not equivalent.
 
@@ -82,44 +83,7 @@ jobs:
         ...
 ```
 
-### Basic example (Erlang/OTP + Elixir, on Ubuntu)
+### Example (Erlang/OTP + Elixir, on Ubuntu)
-
-```yaml
-# create this in .github/workflows/ci.yml
-on: push
-
-jobs:
-  test:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - uses: erlef/setup-beam@v1
-        with:
-          otp-version: '22.2'
-          elixir-version: '1.9.4'
-      - run: mix deps.get
-      - run: mix test
-```
-
-### Basic example (Erlang/OTP + `rebar3`, on Ubuntu)
-
-```yaml
-# create this in .github/workflows/ci.yml
-on: push
-
-jobs:
-  test:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - uses: erlef/setup-beam@v1
-        with:
-          otp-version: '22.2'
-          rebar3-version: '3.14.2'
-      - run: rebar3 ct
-```
-
-### Matrix example (Erlang/OTP + Elixir, on Ubuntu)
 
 ```yaml
 # create this in .github/workflows/ci.yml
@@ -143,7 +107,7 @@ jobs:
       - run: mix test
 ```
 
-### Matrix example (Erlang/OTP + `rebar3`, on Ubuntu)
+### Example (Erlang/OTP + `rebar3`, on Ubuntu)
 
 ```yaml
 # create this in .github/workflows/ci.yml
@@ -166,7 +130,7 @@ jobs:
       - run: rebar3 ct
 ```
 
-### Basic example (Erlang/OTP + `rebar3`, on Windows)
+### Example (Erlang/OTP + `rebar3`, on Windows)
 
 ```yaml
 # create this in .github/workflows/ci.yml
@@ -184,6 +148,25 @@ jobs:
       - run: rebar3 ct
 ```
 
+### Example (Gleam + `rebar3`, on Ubuntu)
+
+```yaml
+# create this in .github/workflows/ci.yml
+on: push
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: erlef/setup-beam@v1
+        with:
+          otp-version: '24'
+          gleam-version: '0.16'
+          rebar3-version: '3.16'
+      - run: rebar3 ct
+```
+
 ## Elixir Problem Matchers
 
 The Elixir Problem Matchers in this repository are adapted from [here](https://github.com/fr1zle/vscode-elixir/blob/45eddb589acd7ac98e0c7305d1c2b24668ca709a/package.json#L70-L118). See [MATCHER_NOTICE](MATCHER_NOTICE.md) for license details.

__tests__/setup-beam.test.js

@@ -11,10 +11,12 @@ const installer = require('../src/installer')
 async function all() {
   await testFailInstallOTP()
   await testFailInstallElixir()
+  await testFailInstallGleam()
   await testFailInstallRebar3()
 
   await testOTPVersions()
   await testElixirVersions()
+  await testGleamVersions()
   await testRebar3Versions()
 
   await testGetVersionFromSpec()
@@ -63,6 +65,20 @@ async function testFailInstallElixir() {
   )
 }
 
+async function testFailInstallGleam() {
+  const gleamVersion = '0.1.3'
+  assert.rejects(
+    async () => {
+      await installer.installGleam(gleamVersion)
+    },
+    (err) => {
+      assert.ok(err instanceof Error)
+      return true
+    },
+    `Installing Gleam ${gleamVersion} is supposed to fail`,
+  )
+}
+
 async function testFailInstallRebar3() {
   const r3Version = '0.14.4'
   assert.rejects(
@@ -197,6 +213,33 @@ async function testElixirVersions() {
   simulateInput('version-type', 'loose')
 }
 
+async function testGleamVersions() {
+  let got
+  let expected
+  let spec
+  let otpVersion
+
+  spec = 'v0.3.0'
+  otpVersion = 'OTP-23'
+  expected = 'v0.3.0'
+  got = await setupBeam.getGleamVersion(spec, otpVersion)
+  assert.deepStrictEqual(got, expected)
+
+  spec = '0.13.2'
+  otpVersion = 'OTP-24'
+  expected = 'v0.13.2'
+  got = await setupBeam.getGleamVersion(spec, otpVersion)
+  assert.deepStrictEqual(got, expected)
+
+  simulateInput('version-type', 'strict')
+  spec = 'v0.14.0-rc2'
+  otpVersion = 'OTP-22'
+  expected = 'v0.14.0-rc2'
+  got = await setupBeam.getGleamVersion(spec, otpVersion)
+  assert.deepStrictEqual(got, expected)
+  simulateInput('version-type', 'loose')
+}
+
 async function testRebar3Versions() {
   let got
   let expected

action.yml

@@ -12,6 +12,8 @@ inputs:
     description: Version range or exact version of Elixir to use
   otp-version:
     description: Version range or exact version of Erlang/OTP to use
+  gleam-version:
+    description: Version range or exact version of Gleam to use
   install-hex:
     description: Whether to install Hex (with Mix)
     default: true
@@ -29,6 +31,8 @@ outputs:
     description: Exact version of Elixir that was installed
   otp-version:
     description: Exact version of Erlang/OTP that was installed
+  gleam-version:
+    description: Exact version of Gleam that was installed
   rebar3-version:
     description: Exact version of rebar3 that was installed
 runs:

dist/index.js

@@ -4618,6 +4618,21 @@ async function installElixir(elixirVersion) {
   }
 }
 
+/**
+ * Install Gleam.
+ *
+ * @param {string} gleamVersion
+ */
+async function installGleam(gleamVersion) {
+  const OS = process.platform
+  if (OS === 'linux') {
+    await exec(__nccwpck_require__.ab + "install-gleam.sh", [gleamVersion])
+  } else if (OS === 'win32') {
+    const script = __nccwpck_require__.ab + "install-gleam.ps1"
+    await exec(`pwsh.exe ${script} -VSN:${gleamVersion}`)
+  }
+}
+
 /**
  * Install rebar3.
  *
@@ -4644,6 +4659,7 @@ function checkPlatform() {
 module.exports = {
   installOTP,
   installElixir,
+  installGleam,
   installRebar3,
   checkPlatform,
 }
@@ -4686,6 +4702,9 @@ async function main() {
     await mix(shouldMixHex, 'hex')
   }
 
+  const gleamSpec = core.getInput('gleam-version', { required: false })
+  await maybeInstallGleam(gleamSpec)
+
   const rebar3Spec = core.getInput('rebar3-version', { required: false })
   await maybeInstallRebar3(rebar3Spec)
 }
@@ -4742,6 +4761,23 @@ async function mix(shouldMix, what) {
   }
 }
 
+async function maybeInstallGleam(gleamSpec) {
+  let installed = false
+
+  if (gleamSpec) {
+    const gleamVersion = await getGleamVersion(gleamSpec)
+    console.log(`##[group]Installing Gleam ${gleamVersion}`)
+    await installer.installGleam(gleamVersion)
+    core.setOutput('gleam-version', gleamVersion)
+    core.addPath(`${process.env.RUNNER_TEMP}/.setup-beam/gleam/bin`)
+    console.log('##[endgroup]')
+
+    installed = true
+  }
+
+  return installed
+}
+
 async function maybeInstallRebar3(rebar3Spec) {
   let installed = false
 
@@ -4830,10 +4866,21 @@ async function getElixirVersion(exSpec0, otpVersion) {
     )
   }
 
-  const DigitStart = new RegExp('^\\d+')
+  return maybePrependWithV(elixirVersionWithOTP, elixirVersion)
-  return DigitStart.test(elixirVersion)
+}
-    ? `v${elixirVersionWithOTP}`
+
-    : elixirVersionWithOTP
+async function getGleamVersion(gleamSpec0) {
+  const gleamSpec = gleamSpec0.match(/^v?(.+)/)
+  const gleamVersions = await getGleamVersions()
+  const gleamVersion = getVersionFromSpec(gleamSpec[1], gleamVersions)
+  if (gleamVersion === null) {
+    throw new Error(
+      `Requested Gleam version (${gleamSpec0}) not found in version list ` +
+        "(should you be using option 'version-type': 'strict'?)",
+    )
+  }
+
+  return maybePrependWithV(gleamVersion, gleamVersion)
 }
 
 async function getRebar3Version(r3Spec) {
@@ -4916,6 +4963,21 @@ async function getElixirVersions() {
   return otpVersionsForElixirMap
 }
 
+async function getGleamVersions() {
+  const resultJSONs = await get(
+    'https://api.github.com/repos/gleam-lang/gleam/releases?per_page=100',
+    [1, 2, 3],
+  )
+  const gleamVersionsListing = []
+  resultJSONs.forEach((resultJSON) => {
+    JSON.parse(resultJSON)
+      .map((x) => x.tag_name)
+      .sort()
+      .forEach((v) => gleamVersionsListing.push(v))
+  })
+  return gleamVersionsListing
+}
+
 async function getRebar3Versions() {
   const resultJSONs = await get(
     'https://api.github.com/repos/erlang/rebar3/releases?per_page=100',
@@ -4959,7 +5021,7 @@ function getVersionFromSpec(spec, versions) {
     }
   }
 
-  return version
+  return version === null || version === undefined ? null : version
 }
 
 function maybeCoerced(v) {
@@ -5066,9 +5128,17 @@ async function get(url0, pageIdxs) {
   return ret
 }
 
+function maybePrependWithV(versionToPrepend, specVersion) {
+  const digitStart = new RegExp('^\\d+')
+  return digitStart.test(specVersion)
+    ? `v${versionToPrepend}`
+    : versionToPrepend
+}
+
 module.exports = {
   getOTPVersion,
   getElixirVersion,
+  getGleamVersion,
   getRebar3Version,
   getVersionFromSpec,
 }

dist/install-elixir.ps1

@@ -15,5 +15,5 @@ New-Item "$DIR_FOR_BIN" -ItemType Directory | Out-Null
 $ProgressPreference="SilentlyContinue"
 Expand-Archive -DestinationPath "${DIR_FOR_BIN}" -Path "${FILE_OUTPUT}"
 $ProgressPreference="Continue"
-Write-Output "Installed Erlang/OTP version follows"
+Write-Output "Installed Elixir version follows"
 & "$DIR_FOR_BIN/bin/iex" "-v" | Write-Output

dist/install-gleam.ps1

@@ -0,0 +1,19 @@
+param([Parameter(Mandatory=$true)][string]$VSN)
+
+$ErrorActionPreference="Stop"
+
+Set-Location $Env:RUNNER_TEMP
+
+$FILE_INPUT="gleam-${VSN}-windows-64bit.zip"
+$FILE_OUTPUT="gleam.zip"
+$DIR_FOR_BIN=".setup-beam/gleam/bin"
+
+$ProgressPreference="SilentlyContinue"
+Invoke-WebRequest "https://github.com/gleam-lang/gleam/releases/download/${VSN}/${FILE_INPUT}" -OutFile "$FILE_OUTPUT"
+$ProgressPreference="Continue"
+New-Item "$DIR_FOR_BIN" -ItemType Directory | Out-Null
+$ProgressPreference="SilentlyContinue"
+Expand-Archive -DestinationPath "${DIR_FOR_BIN}" -Path "${FILE_OUTPUT}"
+$ProgressPreference="Continue"
+Write-Output "Installed Gleam version follows"
+& "$DIR_FOR_BIN/gleam" "--version" | Write-Output

dist/install-gleam.sh

@@ -0,0 +1,17 @@
+#!/bin/bash
+
+set -eo pipefail
+
+cd "$RUNNER_TEMP"
+
+VSN=${1}
+FILE_INPUT=gleam-${VSN}-linux-amd64.tar.gz
+FILE_OUTPUT=gleam.tar.gz
+DIR_FOR_BIN=.setup-beam/gleam/bin
+
+wget -q -O "${FILE_OUTPUT}" "https://github.com/gleam-lang/gleam/releases/download/${VSN}/${FILE_INPUT}"
+mkdir -p "${DIR_FOR_BIN}"
+tar zxf "${FILE_OUTPUT}" -C "${DIR_FOR_BIN}"
+
+echo "Installed Gleam version follows"
+${DIR_FOR_BIN}/gleam --version

src/install-elixir.ps1

@@ -15,5 +15,5 @@ New-Item "$DIR_FOR_BIN" -ItemType Directory | Out-Null
 $ProgressPreference="SilentlyContinue"
 Expand-Archive -DestinationPath "${DIR_FOR_BIN}" -Path "${FILE_OUTPUT}"
 $ProgressPreference="Continue"
-Write-Output "Installed Erlang/OTP version follows"
+Write-Output "Installed Elixir version follows"
 & "$DIR_FOR_BIN/bin/iex" "-v" | Write-Output

src/install-gleam.ps1

@@ -0,0 +1,19 @@
+param([Parameter(Mandatory=$true)][string]$VSN)
+
+$ErrorActionPreference="Stop"
+
+Set-Location $Env:RUNNER_TEMP
+
+$FILE_INPUT="gleam-${VSN}-windows-64bit.zip"
+$FILE_OUTPUT="gleam.zip"
+$DIR_FOR_BIN=".setup-beam/gleam/bin"
+
+$ProgressPreference="SilentlyContinue"
+Invoke-WebRequest "https://github.com/gleam-lang/gleam/releases/download/${VSN}/${FILE_INPUT}" -OutFile "$FILE_OUTPUT"
+$ProgressPreference="Continue"
+New-Item "$DIR_FOR_BIN" -ItemType Directory | Out-Null
+$ProgressPreference="SilentlyContinue"
+Expand-Archive -DestinationPath "${DIR_FOR_BIN}" -Path "${FILE_OUTPUT}"
+$ProgressPreference="Continue"
+Write-Output "Installed Gleam version follows"
+& "$DIR_FOR_BIN/gleam" "--version" | Write-Output

src/install-gleam.sh

@@ -0,0 +1,17 @@
+#!/bin/bash
+
+set -eo pipefail
+
+cd "$RUNNER_TEMP"
+
+VSN=${1}
+FILE_INPUT=gleam-${VSN}-linux-amd64.tar.gz
+FILE_OUTPUT=gleam.tar.gz
+DIR_FOR_BIN=.setup-beam/gleam/bin
+
+wget -q -O "${FILE_OUTPUT}" "https://github.com/gleam-lang/gleam/releases/download/${VSN}/${FILE_INPUT}"
+mkdir -p "${DIR_FOR_BIN}"
+tar zxf "${FILE_OUTPUT}" -C "${DIR_FOR_BIN}"
+
+echo "Installed Gleam version follows"
+${DIR_FOR_BIN}/gleam --version

src/installer.js

@@ -32,6 +32,21 @@ async function installElixir(elixirVersion) {
   }
 }
 
+/**
+ * Install Gleam.
+ *
+ * @param {string} gleamVersion
+ */
+async function installGleam(gleamVersion) {
+  const OS = process.platform
+  if (OS === 'linux') {
+    await exec(path.join(__dirname, 'install-gleam.sh'), [gleamVersion])
+  } else if (OS === 'win32') {
+    const script = path.join(__dirname, 'install-gleam.ps1')
+    await exec(`pwsh.exe ${script} -VSN:${gleamVersion}`)
+  }
+}
+
 /**
  * Install rebar3.
  *
@@ -58,6 +73,7 @@ function checkPlatform() {
 module.exports = {
   installOTP,
   installElixir,
+  installGleam,
   installRebar3,
   checkPlatform,
 }

src/setup-beam.js

@@ -30,6 +30,9 @@ async function main() {
     await mix(shouldMixHex, 'hex')
   }
 
+  const gleamSpec = core.getInput('gleam-version', { required: false })
+  await maybeInstallGleam(gleamSpec)
+
   const rebar3Spec = core.getInput('rebar3-version', { required: false })
   await maybeInstallRebar3(rebar3Spec)
 }
@@ -86,6 +89,23 @@ async function mix(shouldMix, what) {
   }
 }
 
+async function maybeInstallGleam(gleamSpec) {
+  let installed = false
+
+  if (gleamSpec) {
+    const gleamVersion = await getGleamVersion(gleamSpec)
+    console.log(`##[group]Installing Gleam ${gleamVersion}`)
+    await installer.installGleam(gleamVersion)
+    core.setOutput('gleam-version', gleamVersion)
+    core.addPath(`${process.env.RUNNER_TEMP}/.setup-beam/gleam/bin`)
+    console.log('##[endgroup]')
+
+    installed = true
+  }
+
+  return installed
+}
+
 async function maybeInstallRebar3(rebar3Spec) {
   let installed = false
 
@@ -174,10 +194,21 @@ async function getElixirVersion(exSpec0, otpVersion) {
     )
   }
 
-  const DigitStart = new RegExp('^\\d+')
+  return maybePrependWithV(elixirVersionWithOTP, elixirVersion)
-  return DigitStart.test(elixirVersion)
+}
-    ? `v${elixirVersionWithOTP}`
+
-    : elixirVersionWithOTP
+async function getGleamVersion(gleamSpec0) {
+  const gleamSpec = gleamSpec0.match(/^v?(.+)/)
+  const gleamVersions = await getGleamVersions()
+  const gleamVersion = getVersionFromSpec(gleamSpec[1], gleamVersions)
+  if (gleamVersion === null) {
+    throw new Error(
+      `Requested Gleam version (${gleamSpec0}) not found in version list ` +
+        "(should you be using option 'version-type': 'strict'?)",
+    )
+  }
+
+  return maybePrependWithV(gleamVersion, gleamVersion)
 }
 
 async function getRebar3Version(r3Spec) {
@@ -260,6 +291,21 @@ async function getElixirVersions() {
   return otpVersionsForElixirMap
 }
 
+async function getGleamVersions() {
+  const resultJSONs = await get(
+    'https://api.github.com/repos/gleam-lang/gleam/releases?per_page=100',
+    [1, 2, 3],
+  )
+  const gleamVersionsListing = []
+  resultJSONs.forEach((resultJSON) => {
+    JSON.parse(resultJSON)
+      .map((x) => x.tag_name)
+      .sort()
+      .forEach((v) => gleamVersionsListing.push(v))
+  })
+  return gleamVersionsListing
+}
+
 async function getRebar3Versions() {
   const resultJSONs = await get(
     'https://api.github.com/repos/erlang/rebar3/releases?per_page=100',
@@ -303,7 +349,7 @@ function getVersionFromSpec(spec, versions) {
     }
   }
 
-  return version
+  return version === null || version === undefined ? null : version
 }
 
 function maybeCoerced(v) {
@@ -410,9 +456,17 @@ async function get(url0, pageIdxs) {
   return ret
 }
 
+function maybePrependWithV(versionToPrepend, specVersion) {
+  const digitStart = new RegExp('^\\d+')
+  return digitStart.test(specVersion)
+    ? `v${versionToPrepend}`
+    : versionToPrepend
+}
+
 module.exports = {
   getOTPVersion,
   getElixirVersion,
+  getGleamVersion,
   getRebar3Version,
   getVersionFromSpec,
 }

test-projects/gleam_rebar3/.github/workflows/test.yml

@@ -0,0 +1,23 @@
+name: test
+
+on:
+  push:
+    branches:
+      - master
+      - main
+  pull_request:
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2.0.0
+      - uses: gleam-lang/setup-erlang@v1.1.2
+        with:
+          otp-version: 23.2
+      - uses: gleam-lang/setup-gleam@v1.0.2
+        with:
+          gleam-version: 0.16.1
+      - run: rebar3 install_deps
+      - run: rebar3 eunit
+      - run: gleam format --check src test

test-projects/gleam_rebar3/.gitignore

@@ -0,0 +1,21 @@
+*.beam
+*.iml
+*.o
+*.plt
+*.swo
+*.swp
+*~
+.erlang.cookie
+.eunit
+.idea
+.rebar
+.rebar3
+_*
+_build
+docs
+ebin
+erl_crash.dump
+gen
+log
+logs
+rebar3.crashdump

test-projects/gleam_rebar3/README.md

@@ -0,0 +1,24 @@
+# gleam_rebar3
+
+A Gleam project
+
+## Quick start
+
+```sh
+# Run the eunit tests
+rebar3 eunit
+
+# Run the Erlang REPL
+rebar3 shell
+```
+
+## Installation
+
+If [available in Hex](https://rebar3.org/docs/configuration/dependencies/#declaring-dependencies)
+this package can be installed by adding `gleam_rebar3` to your `rebar.config` dependencies:
+
+```erlang
+{deps, [
+    gleam_rebar3
+]}.
+```

test-projects/gleam_rebar3/gleam.toml

@@ -0,0 +1,3 @@
+name = "gleam_rebar3"
+
+# repository = { type = "github", user = "my-user", repo = "gleam_rebar3" }

test-projects/gleam_rebar3/rebar.config

@@ -0,0 +1,12 @@
+{erl_opts, [debug_info]}.
+{src_dirs, ["src", "gen/src"]}.
+
+{profiles, [
+    {test, [{src_dirs, ["src", "test", "gen/src", "gen/test"]}]}
+]}.
+
+{project_plugins, [rebar_gleam]}.
+
+{deps, [
+    {gleam_stdlib, "0.16.0"}
+]}.

test-projects/gleam_rebar3/src/gleam_rebar3.app.src

@@ -0,0 +1,15 @@
+{application, gleam_rebar3,
+ [{description, "A Gleam project"},
+  {vsn, "0.1.0"},
+  {registered, []},
+  {applications,
+   [kernel,
+    stdlib,
+    gleam_stdlib
+   ]},
+  {env,[]},
+  {modules, []},
+
+  {include_files, ["gleam.toml", "gen"]},
+  {links, []}
+]}.

test-projects/gleam_rebar3/src/gleam_rebar3.gleam

@@ -0,0 +1,3 @@
+pub fn hello_world() -> String {
+  "Hello, from gleam_rebar3!"
+}

test-projects/gleam_rebar3/test/gleam_rebar3_test.gleam

@@ -0,0 +1,7 @@
+import gleam_rebar3
+import gleam/should
+
+pub fn hello_world_test() {
+  gleam_rebar3.hello_world()
+  |> should.equal("Hello, from gleam_rebar3!")
+}