1 files changed, 68 insertions, 0 deletions
diff --git a/Differ.java b/Differ.java
new file mode 100644
index 0000000..b53f7fe
--- /dev/null
+++ b/Differ.java
@@ -0,0 +1,68 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2025 The FreeBSD Foundation
+ *
+ * This software was developed by Eilertsens Kodeknekkeri <haraldei@anduin.net>
+ * under sponsorship from The FreeBSD Foundation.
+ */
+
+import java.io.IOException;
+import java.io.StringWriter;
+
+public class Differ
+{
+	private String commit;
+
+	public static void main(String[] args)
+	{
+		var differ = new Differ(args);
+		differ.run();
+	}
+
+	public Differ(String[] args)
+	{
+		commit = args[0];
+	}
+
+	public void run()
+	{
+		try {
+			String[] cmd = {"git", "diff", "--stat", "--name-only", commit};
+			var p = Runtime.getRuntime().exec(cmd);
+
+			p.inputReader()
+				.lines()
+				.filter(filename -> { return includeDiff(filename); })
+				.forEach(filename -> { System.out.println("[ ] " + filename); });
+		} catch (IOException e) {
+			System.err.println("That didn't work: " + e);
+		}
+	}
+
+	private boolean includeDiff(String filename)
+	{
+		try {
+			String[] cmd = {"git", "diff", commit, "--", filename};
+			// System.out.println("[*] Running `" + String.join(" ", cmd) + "`...");
+			var p = Runtime.getRuntime().exec(cmd);
+
+			return p.inputReader()
+				.lines()
+				.anyMatch(line -> { return interestingLine(line); });
+
+		} catch (IOException e) {
+			System.err.println("Could not fetch diff: " + e);
+			return false;
+		}
+	}
+
+	private boolean interestingLine(String line)
+	{
+		var interesting = line.matches("^[+-][^+-].*") && ! line.matches("^.*Copyright.*");
+
+		// System.out.println((interesting ? "! " : "  ") + line);
+
+		return interesting;
+	}
+}