check polkadot for companion pull requests (#5262)

* check_polkadot: move to external script

* check_polkadot: check for companion pr

Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>
Co-authored-by: Bastian Köcher <git@kchr.de>

substrate/.gitlab-ci.yml

@@ -127,6 +127,15 @@ check-line-width:
   allow_failure:                   true
 
 
+check-polkadot:
+  stage:                           build
+  <<:                              *docker-env
+  script:
+    - ./.maintain/gitlab/check_polkadot.sh
+  interruptible:                   true
+  allow_failure:                   true
+
+
 cargo-audit:
   stage:                           test
   <<:                              *docker-env
@@ -410,30 +419,6 @@ check_warnings:
         echo "___No warnings___";
       fi
 
-# Nightly check whether Polkadot 'master' branch builds.
-check_polkadot:
-  stage:                           build
-  <<:                              *docker-env
-  allow_failure:                   true
-  only:
-    - master
-    - schedules
-  script:
-    - SUBSTRATE_PATH=$(pwd)
-    # Clone the current Polkadot master branch into ./polkadot.
-    - git clone --depth 1 https://gitlab.parity.io/parity/polkadot.git
-    - cd polkadot
-    # Make sure we override the crates in native and wasm build
-    - mkdir .cargo
-    - echo "paths = [ \"$SUBSTRATE_PATH\" ]" > .cargo/config
-    - mkdir -p target/debug/wbuild/.cargo
-    - echo "paths = [ \"$SUBSTRATE_PATH\" ]" > target/debug/wbuild/.cargo/config
-    # package, others are updated along the way.
-    - cargo update
-    # Check whether Polkadot 'master' branch builds with this Substrate commit.
-    - time cargo check
-    - cd -
-    - sccache -s
 
 trigger-contracts-ci:
   stage:                           publish

substrate/.maintain/gitlab/check_polkadot.sh

@@ -0,0 +1,80 @@
+#!/bin/sh
+#
+# check if a pr is compatible with polkadot companion pr or master if not 
+# available
+#
+# mark companion pr in the body of the polkadot pr like
+#
+# polkadot companion: paritytech/polkadot#567
+
+
+github_api_substrate_pull_url="https://api.github.com/repos/paritytech/substrate/pulls"
+# use github api v3 in order to access the data without authentication
+github_header="Accept: application/vnd.github.v3+json" 
+
+boldprint () { printf "|\n| \033[1m${@}\033[0m\n|\n" ; }
+boldcat () { printf "|\n"; while read l; do printf "| \033[1m${l}\033[0m\n"; done; printf "|\n" ; }
+
+
+
+boldcat <<-EOT
+
+
+check_polkadot
+==============
+
+this job checks if there is a string in the description of the pr like
+
+polkadot companion: paritytech/polkadot#567
+
+
+it will then run cargo check from this polkadot's branch with substrate code 
+from this pull request.
+
+
+EOT
+
+
+
+SUBSTRATE_PATH=$(pwd)
+
+# Clone the current Polkadot master branch into ./polkadot.
+git clone --depth 1 https://github.com/paritytech/polkadot.git
+
+cd polkadot
+
+# either it's a pull request then check for a companion otherwise use 
+# polkadot:master
+if expr match "${CI_COMMIT_REF_NAME}" '^[0-9]\+$' >/dev/null
+then
+  boldprint "this is pull request no ${CI_COMMIT_REF_NAME}"
+  # get the last reference to a pr in polkadot
+  comppr="$(curl -H "${github_header}" -s ${github_api_substrate_pull_url}/${CI_COMMIT_REF_NAME} \
+    | sed -n -r 's;^[[:space:]]+"body":[[:space:]]+".*polkadot companion: paritytech/polkadot#([0-9]+).*"[^"]+$;\1;p;$!d')"
+  if [ "${comppr}" ]
+  then
+    boldprint "companion pr specified: #${comppr}"
+    git fetch --depth 1 origin refs/pull/${comppr}/head:pr/${comppr}
+    git checkout pr/${comppr}
+  else
+    boldprint "no companion pr declared - building polkadot:master"
+  fi
+else
+  boldprint "this is not a pull request - building polkadot:master"
+fi
+
+# Make sure we override the crates in native and wasm build
+# patching the git path as described in the link below did not test correctly
+# https://doc.rust-lang.org/cargo/reference/overriding-dependencies.html
+mkdir .cargo
+echo "paths = [ \"$SUBSTRATE_PATH\" ]" > .cargo/config
+
+mkdir -p target/debug/wbuild/.cargo
+cp .cargo/config target/debug/wbuild/.cargo/config
+
+# package, others are updated along the way.
+cargo update
+
+# Test Polkadot pr or master branch with this Substrate commit.
+time cargo test --all --release --verbose
+