Merge pull request #651 from phil-opp/post-04-update

Update post_04 branch for new should_panic test

Cargo.toml

@@ -5,7 +5,7 @@ authors = ["Philipp Oppermann <dev@phil-opp.com>"]
 edition = "2018"
 
 [[test]]
-name = "panic_handler"
+name = "should_panic"
 harness = false
 
 [dependencies]

tests/panic_handler.rs

@@ -1,74 +0,0 @@
-#![no_std]
-#![no_main]
-#![feature(panic_info_message)]
-
-use blog_os::{exit_qemu, serial_print, serial_println, QemuExitCode};
-use core::{
-    fmt::{self, Write},
-    panic::PanicInfo,
-};
-
-const MESSAGE: &str = "Example panic message from panic_handler test";
-const PANIC_LINE: u32 = 17; // adjust this when moving the `panic!` call
-
-#[no_mangle]
-pub extern "C" fn _start() -> ! {
-    serial_print!("panic_handler... ");
-    panic!(MESSAGE); // must be in line `PANIC_LINE`
-}
-
-#[panic_handler]
-fn panic(info: &PanicInfo) -> ! {
-    check_location(info);
-    check_message(info);
-
-    serial_println!("[ok]");
-    exit_qemu(QemuExitCode::Success);
-    loop {}
-}
-
-fn fail(error: &str) -> ! {
-    serial_println!("[failed]");
-    serial_println!("{}", error);
-    exit_qemu(QemuExitCode::Failed);
-    loop {}
-}
-
-fn check_location(info: &PanicInfo) {
-    let location = info.location().unwrap_or_else(|| fail("no location"));
-    if location.file() != file!() {
-        fail("file name wrong");
-    }
-    if location.line() != PANIC_LINE {
-        fail("file line wrong");
-    }
-}
-
-fn check_message(info: &PanicInfo) {
-    let message = info.message().unwrap_or_else(|| fail("no message"));
-    let mut compare_message = CompareMessage { expected: MESSAGE };
-    write!(&mut compare_message, "{}", message).unwrap_or_else(|_| fail("write failed"));
-    if compare_message.expected.len() != 0 {
-        fail("message shorter than expected message");
-    }
-}
-
-/// Compares a `fmt::Arguments` instance with the `MESSAGE` string
-///
-/// To use this type, write the `fmt::Arguments` instance to it using the
-/// `write` macro. If the message component matches `MESSAGE`, the `expected`
-/// field is the empty string.
-struct CompareMessage {
-    expected: &'static str,
-}
-
-impl fmt::Write for CompareMessage {
-    fn write_str(&mut self, s: &str) -> fmt::Result {
-        if self.expected.starts_with(s) {
-            self.expected = &self.expected[s.len()..];
-        } else {
-            fail("message not equal to expected message");
-        }
-        Ok(())
-    }
-}

tests/should_panic.rs

@@ -0,0 +1,25 @@
+#![no_std]
+#![no_main]
+
+use blog_os::{exit_qemu, serial_print, serial_println, QemuExitCode};
+use core::panic::PanicInfo;
+
+#[no_mangle]
+pub extern "C" fn _start() -> ! {
+    should_fail();
+    serial_println!("[test did not panic]");
+    exit_qemu(QemuExitCode::Failed);
+    loop {}
+}
+
+fn should_fail() {
+    serial_print!("should_fail... ");
+    assert_eq!(0, 1);
+}
+
+#[panic_handler]
+fn panic(_info: &PanicInfo) -> ! {
+    serial_println!("[ok]");
+    exit_qemu(QemuExitCode::Success);
+    loop {}
+}