Fix a bug when running on upstream branch, and add some tests

.circleci/config.yml

@@ -0,0 +1,102 @@
+version: 2.1
+
+refs:
+  test_filter: &test_filter
+    filters:
+      branches:
+        only: testing
+
+workflows:
+  version: 2.0
+
+#  publish-dev:
+#    jobs:
+#      - publish
+
+  ci:
+    jobs:
+      - test_orb_file_changed: *test_filter
+      - test_orb_no_file_changed: *test_filter
+      - test_orb_on_upstream: *test_filter
+
+orbs:
+  multirepo: dnephin/multirepo@dev:testing
+
+executors:
+  bash:
+    docker:
+    - image: bash:4
+
+commands:
+  # temporary command while the official circleci/cli orb dependencies are cleaned up.
+  install-cli:
+    steps:
+      - run:
+          name: download
+          command: |
+            export releases=https://github.com/CircleCI-Public/circleci-cli/releases
+            export version=0.1.5432
+            wget -qO- $releases/download/v${version}/circleci-cli_${version}_linux_amd64.tar.gz | \
+              tar -zx circleci-cli_${version}_linux_amd64/circleci
+            mv circleci*/* /bin
+
+  install-git:
+    steps:
+      - run:
+          name: "Install git"
+          command: |
+            command -v git && exit
+            command -v apk && apk add --no-cache --no-progress git
+
+  setup:
+    steps:
+      - install-git
+      - checkout
+      - run: test/bin/fake-circleci-agent
+
+jobs:
+  publish:
+    executor: bash
+    parameters:
+      tag:
+        type: string
+        default: "dev:testing"
+    steps:
+      - install-cli
+      - install-git
+      - run: circleci orb validate orb.yaml
+      - run: circleci orb publish orb.yaml dnephin/multirepo@<< parameters.tag >>
+      - run: |
+          git co -b local
+          git push origin local:stage
+
+  test_orb_file_changed:
+    executor: bash
+    environment:
+      TESTDIR: /tmp/testdir
+    steps:
+      - setup
+      - multirepo/run-job-for-paths:
+          paths: orb.yaml
+      - run: test/bin/expect-no-halt
+
+  test_orb_no_file_changed:
+    executor: bash
+    environment:
+      TESTDIR: /tmp/testdir
+    steps:
+      - setup
+      - multirepo/run-job-for-paths:
+          paths: testdata/no-changes-here
+      - run: test/bin/expect-halted
+
+  test_orb_on_upstream:
+    executor: bash
+    environment:
+      TESTDIR: /tmp/testdir
+    steps:
+      - setup
+      - multirepo/run-job-for-paths:
+          paths: orb.yaml
+          upstream_branch: $CIRCLE_SHA1
+      - run: test/bin/expect-no-halt

orb.yaml

@@ -7,8 +7,10 @@ description: |
 commands:
   run-job-for-paths:
     description: |
-      Continue running the job if any files in the paths have been modified relative
-      to the last commit shared with the upstream git branch.
+      Continue running the job if any file in paths has been modified since
+      the last commit shared with the upstream git branch (default: origin/master).
+
+      This command must be run after `checkout`.
 
       This command allows you to skip all of the subsequent steps in a job so that any
       repository with multiple workflows, or multiple flows within a single
@@ -36,12 +38,22 @@ commands:
         default: "$PWD"
     steps:
       - run:
-          name: Check if task should run
+          name: Check if job should run
           command: |
             cd << parameters.working_directory >>
 
             upstream="$(git merge-base HEAD << parameters.upstream_branch >>)"
             echo "Comparing to upstream commit $upstream"
+
+            if [[ "$(git rev-parse HEAD)" == "$upstream" ]]; then
+              echo "HEAD matches upstream, running with no diff"
+              exit 0
+            fi
+
+            if [[ -z "$upstream" ]]; then
+              echo "git merge-base failed"
+              exit 1
+            fi
 
             # Print the diff
             PAGER=cat git diff --stat=80 $upstream -- << parameters.paths >>
@@ -51,5 +63,3 @@ commands:
               echo "Skipping job, no files modified"
               circleci-agent step halt
             fi
-
-

test/bin/expect-halted

@@ -0,0 +1,12 @@
+#!/usr/bin/env bash
+set -eu -o pipefail
+testdir="${TESTDIR-/tmp/testdir}"
+
+if [[ -f "$testdir/halted" ]]; then
+  echo "Task was halted"
+  rm "$testdir/halted"
+  exit 0
+fi
+
+echo "Task was not halted"
+exit 1

test/bin/expect-no-halt

@@ -0,0 +1,12 @@
+#!/usr/bin/env bash
+set -eu -o pipefail
+testdir="${TESTDIR-/tmp/testdir}"
+
+if [[ ! -f "$testdir/halted" ]]; then
+  echo "Task was not halted"
+  exit 0
+fi
+
+rm "$testdir/halted"
+echo "Task was halted"
+exit 1

test/bin/fake-circleci-agent

@@ -0,0 +1,12 @@
+#!/usr/bin/env bash
+set -eu -o pipefail
+testdir="${TESTDIR-/tmp/testdir}"
+mkdir -p $testdir ~/bin
+
+fake=~/bin/circleci-agent
+cat > $fake <<FAKE
+  touch "$testdir/halted"
+FAKE
+chmod +x $fake
+
+echo "export PATH=$(dirname $fake):$PATH" >> $BASH_ENV