Retain original release info if the keys are not set

README.md

@@ -185,7 +185,12 @@ The following are optional as `step.with` keys
 | `fail_on_unmatched_files` | Boolean | Indicator of whether to fail if any of the `files` globs match nothing                              |
 | `target_commitish`        | String  | Commitish value that determines where the Git tag is created from. Can be any branch or commit SHA. |
 
-💡When providing a `body` and `body_path` at the same time, `body_path` will be attempted first, then falling back on `body` if the path can not be read from.
+💡 When providing a `body` and `body_path` at the same time, `body_path` will be
+attempted first, then falling back on `body` if the path can not be read from.
+
+💡 When the release info keys (such as `name`, `body`, `draft`, `prerelease`, etc.)
+are not explicitly set and there is already an existing release for the tag, the
+release will retain its original info.
 
 #### outputs
 

__tests__/util.test.ts

@@ -87,8 +87,8 @@ describe("util", () => {
         github_token: "",
         input_body: undefined,
         input_body_path: undefined,
-        input_draft: false,
-        input_prerelease: false,
+        input_draft: undefined,
+        input_prerelease: undefined,
         input_files: [],
         input_name: undefined,
         input_tag_name: undefined,
@@ -109,8 +109,8 @@ describe("util", () => {
           github_token: "",
           input_body: undefined,
           input_body_path: undefined,
-          input_draft: false,
-          input_prerelease: false,
+          input_draft: undefined,
+          input_prerelease: undefined,
           input_files: [],
           input_name: undefined,
           input_tag_name: undefined,
@@ -119,6 +119,28 @@ describe("util", () => {
         }
       );
     });
+    it("parses basic config with draft and prerelease", () => {
+      assert.deepStrictEqual(
+        parseConfig({
+          INPUT_DRAFT: "false",
+          INPUT_PRERELEASE: "true"
+        }),
+        {
+          github_ref: "",
+          github_repository: "",
+          github_token: "",
+          input_body: undefined,
+          input_body_path: undefined,
+          input_draft: false,
+          input_prerelease: true,
+          input_files: [],
+          input_name: undefined,
+          input_tag_name: undefined,
+          input_fail_on_unmatched_files: false,
+          input_target_commitish: undefined
+        }
+      );
+    });
   });
   describe("isTag", () => {
     it("returns true for tags", async () => {

src/github.ts

@@ -16,8 +16,11 @@ export interface Release {
   upload_url: string;
   html_url: string;
   tag_name: string;
+  name: string;
   body: string;
   target_commitish: string;
+  draft: boolean;
+  prerelease: boolean;
 }
 
 export interface Releaser {
@@ -179,11 +182,24 @@ export const release = async (
     } else {
       target_commitish = existingRelease.data.target_commitish;
     }
+
     const tag_name = tag;
-    const name = config.input_name || tag;
-    const body = `${existingRelease.data.body}\n${releaseBody(config)}`;
-    const draft = config.input_draft;
-    const prerelease = config.input_prerelease;
+    const name = config.input_name || existingRelease.data.name || tag;
+
+    let body: string = "";
+    if (existingRelease.data.body) body += existingRelease.data.body;
+    let workflowBody = releaseBody(config);
+    if (existingRelease.data.body && workflowBody) body += "\n";
+    if (workflowBody) body += workflowBody;
+
+    const draft =
+      config.input_draft !== undefined
+        ? config.input_draft
+        : existingRelease.data.draft;
+    const prerelease =
+      config.input_prerelease !== undefined
+        ? config.input_prerelease
+        : existingRelease.data.prerelease;
 
     const release = await releaser.updateRelease({
       owner,

src/util.ts

@@ -49,8 +49,10 @@ export const parseConfig = (env: Env): Config => {
     input_body: env.INPUT_BODY,
     input_body_path: env.INPUT_BODY_PATH,
     input_files: parseInputFiles(env.INPUT_FILES || ""),
-    input_draft: env.INPUT_DRAFT === "true",
-    input_prerelease: env.INPUT_PRERELEASE == "true",
+    input_draft: env.INPUT_DRAFT ? env.INPUT_DRAFT === "true" : undefined,
+    input_prerelease: env.INPUT_PRERELEASE
+      ? env.INPUT_PRERELEASE == "true"
+      : undefined,
     input_fail_on_unmatched_files: env.INPUT_FAIL_ON_UNMATCHED_FILES == "true",
     input_target_commitish: env.INPUT_TARGET_COMMITISH
   };