Support built-in diff drivers for hunk header function names

The regexes defined for each built-in driver will be used to determine
the function name for a hunk header. Each driver can specify a list of
regexes to negate and match. They can also define pattern compilation
flags if needed. These drivers only apply to text files with unified
patch type.

Following built-in drivers have been added:
- cpp
- dts
- java
- python
- rust

Support for more languages can be added as needed to match the cgit
implementation.

Change-Id: Ice5430bfed7e4aaf9f00e52e44402479984953c5

5 files changed, 158 insertions, 0 deletions

diff --git a/org.eclipse.jgit.test/tst-rsrc/org/eclipse/jgit/test/resources/greeting.c b/org.eclipse.jgit.test/tst-rsrc/org/eclipse/jgit/test/resources/greeting.c
new file mode 100644
index 0000000000..3661160921
--- /dev/null
+++ b/org.eclipse.jgit.test/tst-rsrc/org/eclipse/jgit/test/resources/greeting.c
@@ -0,0 +1,43 @@
+#include <stdio.h>
+#include <string.h>
+#include <ctype.h>
+
+void getGreeting(char *result, const char *name) {
+    sprintf(result, "Hello, %s!", name);
+}
+
+void getFarewell(char *result, const char *name) {
+    sprintf(result, "Goodbye, %s. Have a great day!", name);
+}
+
+void toLower(char *str) {
+    for (int i = 0; str[i]; i++) {
+        str[i] = tolower(str[i]);
+    }
+}
+
+void getPersonalizedGreeting(char *result, const char *name, const char *timeOfDay) {
+    char timeOfDayLower[50];
+    strcpy(timeOfDayLower, timeOfDay);
+    toLower(timeOfDayLower);
+    if (strcmp(timeOfDayLower, "morning") == 0) {
+        sprintf(result, "Good morning, %s", name);
+    } else if (strcmp(timeOfDayLower, "afternoon") == 0) {
+        sprintf(result, "Good afternoon, %s", name);
+    } else if (strcmp(timeOfDayLower, "evening") == 0) {
+        sprintf(result, "Good evening, %s", name);
+    } else {
+        sprintf(result, "Good day, %s", name);
+    }
+}
+
+int main() {
+    char result[100];
+    getGreeting(result, "foo");
+    printf("%s\\n", result);
+    getFarewell(result, "bar");
+    printf("%s\\n", result);
+    getPersonalizedGreeting(result, "baz", "morning");
+    printf("%s\\n", result);
+    return 0;
+}
diff --git a/org.eclipse.jgit.test/tst-rsrc/org/eclipse/jgit/test/resources/greeting.javasource b/org.eclipse.jgit.test/tst-rsrc/org/eclipse/jgit/test/resources/greeting.javasource
new file mode 100644
index 0000000000..9659685c63
--- /dev/null
+++ b/org.eclipse.jgit.test/tst-rsrc/org/eclipse/jgit/test/resources/greeting.javasource
@@ -0,0 +1,37 @@
+public class Greeting {
+    public String getGreeting(String name) {
+        String msg = "Hello, " + name + "!";
+        return msg;
+    }
+
+    public String getFarewell(String name) {
+        String msg = "Goodbye, " + name + ". Have a great day!";
+        return msg;
+    }
+
+    public String getPersonalizedGreeting(String name, String timeOfDay) {
+        String msg;
+        switch (timeOfDay.toLowerCase()) {
+        case "morning":
+            msg = "Good morning, " + name;
+            break;
+        case "afternoon":
+            msg = "Good afternoon, " + name;
+            break;
+        case "evening":
+            msg = "Good evening, " + name;
+            break;
+        default:
+            msg = "Good day, " + name;
+            break;
+        }
+        return msg;
+    }
+
+    public static void main(String[] args) {
+        Greeting greeting = new Greeting();
+        System.out.println(greeting.getGreeting("foo"));
+        System.out.println(greeting.getFarewell("bar"));
+        System.out.println(greeting.getPersonalizedGreeting("baz", "morning"));
+    }
+}
diff --git a/org.eclipse.jgit.test/tst-rsrc/org/eclipse/jgit/test/resources/greeting.py b/org.eclipse.jgit.test/tst-rsrc/org/eclipse/jgit/test/resources/greeting.py
new file mode 100644
index 0000000000..9eda6cd8fe
--- /dev/null
+++ b/org.eclipse.jgit.test/tst-rsrc/org/eclipse/jgit/test/resources/greeting.py
@@ -0,0 +1,26 @@
+class Greeting:
+    def get_greeting(self, name):
+        greeting_message = f"Hello, {name}!"
+        return greeting_message
+
+    def get_farewell(self, name):
+        farewell_message = f"Goodbye, {name}. Have a great day!"
+        return farewell_message
+
+    def get_personalized_greeting(self, name, time_of_day):
+        time_of_day = time_of_day.lower()
+        if time_of_day == "morning":
+            personalized_message = f"Good morning, {name}"
+        elif time_of_day == "afternoon":
+            personalized_message = f"Good afternoon, {name}"
+        elif time_of_day == "evening":
+            personalized_message = f"Good evening, {name}"
+        else:
+            personalized_message = f"Good day, {name}"
+        return personalized_message
+
+if __name__ == "__main__":
+    greeting = Greeting()
+    print(greeting.get_greeting("foo"))
+    print(greeting.get_farewell("bar"))
+    print(greeting.get_personalized_greeting("baz", "morning"))
diff --git a/org.eclipse.jgit.test/tst-rsrc/org/eclipse/jgit/test/resources/greeting.rs b/org.eclipse.jgit.test/tst-rsrc/org/eclipse/jgit/test/resources/greeting.rs
new file mode 100644
index 0000000000..a3aa5cbe7c
--- /dev/null
+++ b/org.eclipse.jgit.test/tst-rsrc/org/eclipse/jgit/test/resources/greeting.rs
@@ -0,0 +1,27 @@
+struct Greeting;
+
+impl Greeting {
+    fn get_greeting(&self, name: &str) -> String {
+        format!("Hello, {}!", name)
+    }
+
+    fn get_farewell(&self, name: &str) -> String {
+        format!("Goodbye, {}. Have a great day!", name)
+    }
+
+    fn get_personalized_greeting(&self, name: &str, time_of_day: &str) -> String {
+        match time_of_day.to_lowercase().as_str() {
+            "morning" => format!("Good morning, {}", name),
+            "afternoon" => format!("Good afternoon, {}", name),
+            "evening" => format!("Good evening, {}", name),
+            _ => format!("Good day, {}", name),
+        }
+    }
+}
+
+fn main() {
+    let greeting = Greeting;
+    println!("{}", greeting.get_greeting("foo"));
+    println!("{}", greeting.get_farewell("bar"));
+    println!("{}", greeting.get_personalized_greeting("baz", "morning"));
+}
diff --git a/org.eclipse.jgit.test/tst-rsrc/org/eclipse/jgit/test/resources/sample.dtsi b/org.eclipse.jgit.test/tst-rsrc/org/eclipse/jgit/test/resources/sample.dtsi
new file mode 100644
index 0000000000..6aa4ecdd4c
--- /dev/null
+++ b/org.eclipse.jgit.test/tst-rsrc/org/eclipse/jgit/test/resources/sample.dtsi
@@ -0,0 +1,25 @@
+/dts-v1/;
+
+/ {
+	model = "Example Board";
+	compatible = "example,board";
+	cpus {
+		cpu@0 {
+			device_type = "cpu";
+			compatible = "arm,cortex-a9";
+			reg = <0>;
+		};
+	};
+
+	memory {
+		device_type = "memory";
+		reg = <0x80000000 0x20000000>;
+	};
+
+	uart0: uart@101f1000 {
+		compatible = "ns16550a";
+		reg = <0x101f1000 0x1000>;
+		interrupts = <5>;
+		clock-frequency = <24000000>;
+	};
+};