Use Elixir 1.12 with Erlang 24 in CI

.github/workflows/oci.yaml

@@ -71,10 +71,14 @@ jobs:
         run: |
           bazelisk build :otp_version --config=rbe-${{ steps.load-info.outputs.otp_major }}
           if [ ! "$(cat bazel-bin/otp_version.txt)" == "${{ steps.load-info.outputs.otp }}" ]; then
+            echo "The version of erlang specified via bazel is $(cat bazel-bin/otp_version.txt),
+            echo "but ${{ steps.load-info.outputs.otp }} is expected."
             exit 1
           fi
           bazelisk build :elixir_version --config=rbe-${{ steps.load-info.outputs.otp_major }}
           if [ ! "$(cat bazel-bin/elixir_version.txt)" == "${{ steps.load-info.outputs.elixir }}" ]; then
+            echo "The version of elixir specified via bazel is $(cat bazel-bin/elixir_version.txt),
+            echo "but ${{ steps.load-info.outputs.elixir }} is expected."
             exit 1
           fi
 

WORKSPACE.bazel

@@ -73,6 +73,7 @@ register_toolchains(
     "//bazel/toolchains:erlang_toolchain_git_master",
     "//bazel/toolchains:elixir_toolchain_external",
     "//bazel/toolchains:elixir_toolchain_1_10",
+    "//bazel/toolchains:elixir_toolchain_1_12",
     "//bazel/toolchains:elixir_toolchain_1_13",
 )
 

bazel/platforms/BUILD.bazel

@@ -21,6 +21,11 @@ constraint_value(
     constraint_setting = ":elixir_version",
 )
 
+constraint_value(
+    name = "elixir_1_12",
+    constraint_setting = ":elixir_version",
+)
+
 constraint_value(
     name = "elixir_1_13",
     constraint_setting = ":elixir_version",
@@ -48,7 +53,7 @@ platform(
     name = "erlang_24_platform",
     constraint_values = [
         "@rules_erlang//platforms:erlang_24",
-        ":elixir_1_13",
+        ":elixir_1_12",
     ],
     parents = ["@rbe//config:platform"],
 )

bazel/toolchains/BUILD.bazel

@@ -44,6 +44,11 @@ elixir_toolchain_from_github_release(
     version = "1.10.4",
 )
 
+elixir_toolchain_from_github_release(
+    name_suffix = "_1_12",
+    version = "1.12.3",
+)
+
 elixir_toolchain_from_github_release(
     name_suffix = "_1_13",
     version = "1.13.4",