revert MissingPushHook checks changes

lib/workflow.js

@@ -34,6 +34,9 @@ const core = __importStar(require("@actions/core"));
 const yaml = __importStar(require("js-yaml"));
 const api = __importStar(require("./api-client"));
 const util_1 = require("./util");
+function isObject(o) {
+    return o !== null && typeof o === "object";
+}
 const GLOB_PATTERN = new RegExp("(\\*\\*?)");
 function escapeRegExp(string) {
     return string.replace(/[.*+?^${}()|[\]\\]/g, "\\$&"); // $& means the whole matched string
@@ -71,6 +74,7 @@ function toCodedErrors(errors) {
 // code to send back via status report
 // message to add as a warning annotation to the run
 exports.WorkflowErrors = toCodedErrors({
+    MissingPushHook: `Please specify an on.push hook.`,
     CheckoutWrongHead: `git checkout HEAD^2 is no longer necessary. Please remove this step as Code Scanning recommends analyzing the merge commit for best results.`,
 });
 function getWorkflowErrors(doc) {
@@ -93,6 +97,32 @@ function getWorkflowErrors(doc) {
             }
         }
     }
+    let missingPush = false;
+    if (doc.on === undefined) {
+        // this is not a valid config
+    }
+    else if (typeof doc.on === "string") {
+        if (doc.on === "pull_request") {
+            missingPush = true;
+        }
+    }
+    else if (Array.isArray(doc.on)) {
+        const hasPush = doc.on.includes("push");
+        const hasPullRequest = doc.on.includes("pull_request");
+        if (hasPullRequest && !hasPush) {
+            missingPush = true;
+        }
+    }
+    else if (isObject(doc.on)) {
+        const hasPush = Object.prototype.hasOwnProperty.call(doc.on, "push");
+        const hasPullRequest = Object.prototype.hasOwnProperty.call(doc.on, "pull_request");
+        if (!hasPush && hasPullRequest) {
+            missingPush = true;
+        }
+    }
+    if (missingPush) {
+        errors.push(exports.WorkflowErrors.MissingPushHook);
+    }
     return errors;
 }
 exports.getWorkflowErrors = getWorkflowErrors;