Merge pull request #56 from wilzbach/user-title-labelling

Fix #53 - recognize common attributes in the PR title

Author: andralex

source/dlangbot/app.d

@@ -152,7 +152,7 @@ void githubHook(HTTPServerRequest req, HTTPServerResponse res)
             if (json["pull_request"]["merged"].get!bool)
                 action = "merged";
             goto case;
-        case "opened", "reopened", "synchronize", "labeled":
+        case "opened", "reopened", "synchronize", "labeled", "edited":
 
             auto pullRequest = json["pull_request"].deserializeJson!PullRequest;
             runTaskHelper(toDelegate(&handlePR), action, pullRequest);
@@ -189,6 +189,9 @@ void handlePR(string action, PullRequest pr)
         }
     }
 
+    if (action == "opened" || action == "edited")
+        checkTitleForLabels(pr);
+
     // we only query the commits once
     if (commits is null)
         commits = ghGetRequest(pr.commitsURL).readJson[];

source/dlangbot/github.d

@@ -237,7 +237,7 @@ void checkAndRemoveLabels(Json[] labels, in ref PullRequest pr, in string[] toRe
         .each!(l => pr.removeLabel(l));
 }
 
-void addLabels(in ref PullRequest pr, string[] labels)
+void addLabels(in ref PullRequest pr, inout string[] labels)
 {
     auto labelUrl = "%s/repos/%s/issues/%d/labels"
             .format(githubAPIURL, pr.repoSlug, pr.number);
@@ -286,4 +286,39 @@ void searchForAutoMergePrs(string repoSlug)
     }
 }
 
+/**
+Allows contributors to use [<label>] messages in the title.
+If they are part of a pre-defined, allowed list, the bot will add the
+respective label.
+*/
+void checkTitleForLabels(in ref PullRequest pr)
+{
+    import std.algorithm.iteration : splitter;
+    import std.regex;
+    import std.string : strip, toLower;
+
+    static labelRe = regex(`\[(.*)\]`);
+    string[] userLabels;
+    foreach (m; pr.title.matchAll(labelRe))
+    {
+        foreach (el; m[1].splitter(","))
+            userLabels ~= el;
+    }
 
+    const string[string] userLabelsMap = [
+        "trivial": "trivial",
+        "wip": "WIP"
+    ];
+
+    auto mappedLabels = userLabels
+                            .sort()
+                            .uniq
+                            .map!strip
+                            .map!toLower
+                            .filter!(l => l in userLabelsMap)
+                            .map!(l => userLabelsMap[l])
+                            .array;
+
+    if (mappedLabels.length)
+        pr.addLabels(mappedLabels);
+}

test/labels.d

@@ -86,3 +86,43 @@ unittest
         }
     );
 }
+
+// test whether users can label their PR via the title
+unittest
+{
+    setAPIExpectations(
+        "/github/repos/dlang/dmd/pulls/6359/commits", (ref Json json) {
+            json = Json.emptyArray;
+        },
+        "/github/repos/dlang/dmd/issues/6359/comments",
+        "/github/repos/dlang/dmd/issues/6359/labels",
+        (scope HTTPServerRequest req, scope HTTPServerResponse res) {
+            assert(req.method == HTTPMethod.POST);
+            assert(req.json.deserializeJson!(string[]) == ["trivial"]);
+            res.writeVoidBody;
+        }
+    );
+
+    postGitHubHook("dlang_dmd_open_6359.json", "pull_request",
+        (ref Json j, scope HTTPClientRequest req){
+            j["pull_request"]["title"] = "[Trivial] foo bar";
+        }
+    );
+}
+
+// test that not only a selection of labels is accepted
+unittest
+{
+    setAPIExpectations(
+        "/github/repos/dlang/dmd/pulls/6359/commits", (ref Json json) {
+            json = Json.emptyArray;
+        },
+        "/github/repos/dlang/dmd/issues/6359/comments",
+    );
+
+    postGitHubHook("dlang_dmd_open_6359.json", "pull_request",
+        (ref Json j, scope HTTPClientRequest req){
+            j["pull_request"]["title"] = "[auto-merge] foo bar";
+        }
+    );
+}

test/utils.d

@@ -9,7 +9,7 @@ public import vibe.http.common : HTTPMethod;
 public import vibe.http.client : HTTPClientRequest;
 public import vibe.http.server : HTTPServerRequest, HTTPServerResponse;
 public import std.functional : toDelegate;
-public import vibe.data.json : Json;
+public import vibe.data.json : deserializeJson, Json;
 public import std.datetime : SysTime;
 
 // existing dlang bot comment -> update comment