Override OTP version when specified in Elixir spec (#330)

dist/index.js

@@ -9284,7 +9284,13 @@ async function getOTPVersion(otpSpec0, osVersion) {
 
 async function getElixirVersion(exSpec0, otpVersion0) {
   const otpVersion = otpVersion0.match(/^([^-]+-)?(.+)$/)[2]
-  const otpVersionMajor = otpVersion.match(/^([^.]+).*$/)[1]
+  let otpVersionMajor = otpVersion.match(/^([^.]+).*$/)[1]
+
+  const userSuppliedOtp = exSpec0.match(/-otp-(\d+)/)?.[1] ?? null
+
+  if (userSuppliedOtp && isVersion(userSuppliedOtp)) {
+    otpVersionMajor = userSuppliedOtp
+  }
 
   const [otpVersionsForElixirMap, elixirVersions] = await getElixirVersions()
   const spec = exSpec0.replace(/-otp-.*$/, '')

src/setup-beam.js

@@ -184,7 +184,13 @@ async function getOTPVersion(otpSpec0, osVersion) {
 
 async function getElixirVersion(exSpec0, otpVersion0) {
   const otpVersion = otpVersion0.match(/^([^-]+-)?(.+)$/)[2]
-  const otpVersionMajor = otpVersion.match(/^([^.]+).*$/)[1]
+  let otpVersionMajor = otpVersion.match(/^([^.]+).*$/)[1]
+
+  const userSuppliedOtp = exSpec0.match(/-otp-(\d+)/)?.[1] ?? null
+
+  if (userSuppliedOtp && isVersion(userSuppliedOtp)) {
+    otpVersionMajor = userSuppliedOtp
+  }
 
   const [otpVersionsForElixirMap, elixirVersions] = await getElixirVersions()
   const spec = exSpec0.replace(/-otp-.*$/, '')

test/setup-beam.test.js

@@ -511,6 +511,12 @@ describe('.getOTPVersion(_) - Elixir', () => {
     got = await setupBeam.getElixirVersion(spec, otpVersion)
     assert.deepStrictEqual(got, expected)
 
+    spec = '1.16.2-otp-26'
+    otpVersion = 'OTP-27'
+    expected = 'v1.16.2-otp-26'
+    got = await setupBeam.getElixirVersion(spec, otpVersion)
+    assert.deepStrictEqual(got, expected)
+
     spec = '1.12.1'
     otpVersion = 'OTP-24.0.2'
     expected = 'v1.12.1-otp-24'