pull_request.rs: Add `pull_request_opened_or_synchronized()`

A new function that, given the parsed JSON from a pull request webhook,
tells us whether the pull request was "opened" or "synchronize"d with a
boolean.

This will enable us to only update commit statuses when actions on the
pull request result in new commits being available. Otherwise, we don't
want to set a commit status that we've already set before.

1 files changed, 60 insertions, 0 deletions

diff --git a/src/pull_request.rs b/src/pull_request.rs
index fb06544..c4081f4 100644
--- a/src/pull_request.rs
+++ b/src/pull_request.rs
@@ -42,6 +42,18 @@ impl CommitRef {
     }
 }
 
+pub fn pull_request_opened_or_synchronized(
+    mut github_push_event: json::JsonValue
+) -> bool {
+    let action = github_push_event["action"].take_string().unwrap_or_default();
+
+    if action == "opened" || action == "synchronize" {
+        return true
+    }
+
+    false
+}
+
 
 #[cfg(test)]
 mod tests {
@@ -473,4 +485,52 @@ mod tests {
         assert_eq!(commit_ref.sha, "0d1a26e67d8f5eaf1f6ba5c57fc3c7d91ac0fd1c");
         assert_eq!(commit_ref.branch, "changes");
     }
+
+    #[test]
+    fn pull_request_opened_or_synchronized_returns_true_when_opened() {
+        let payload = r#"{
+            "action": "opened"
+        }"#;
+
+        let json = json::parse(payload)
+            .expect("Failed to parse payload.");
+
+        assert_eq!(
+            pull_request_opened_or_synchronized(json),
+            true
+        );
+    }
+
+    #[test]
+    fn pull_request_opened_or_synchronized_returns_true_when_synchronized() {
+        let payload = r#"{
+            "action": "synchronize"
+        }"#;
+
+        let json = json::parse(payload)
+            .expect("Failed to parse payload.");
+
+        assert_eq!(
+            pull_request_opened_or_synchronized(json),
+            true
+        );
+    }
+
+    #[test]
+    fn pull_request_opened_or_synchronized_returns_false_when_not_opened_or_synchronized() {
+        // "assigned", "unassigned", "review_requested",
+        // "review_request_removed", "labeled", "unlabeled", "opened",
+        // "edited", "closed", or "reopened"
+        let payload = r#"{
+            "action": "review_requested"
+        }"#;
+
+        let json = json::parse(payload)
+            .expect("Failed to parse payload.");
+
+        assert_eq!(
+            pull_request_opened_or_synchronized(json),
+            false
+        );
+    }
 }