Add a representation of a parsed test case file.

The new exported function `parse_test()` will produce it eventually.

src/libreader/testfile.rs

@@ -0,0 +1,40 @@
+//! Data structures representing a parsed test file.
+//!
+//! A test file is a `.cton` file which contains test commands and settings for running a
+//! file-based test case.
+//!
+
+use cretonne::ir::Function;
+use cretonne::ir::entities::AnyEntity;
+use testcommand::TestCommand;
+
+/// A parsed test case.
+///
+/// This is the result of parsing a `.cton` file which contains a number of test commands followed
+/// by the functions that should be tested.
+#[derive(Debug)]
+pub struct TestFile<'a> {
+    pub commands: Vec<TestCommand<'a>>,
+    pub functions: Vec<DetailedFunction<'a>>,
+}
+
+/// A function parsed from a text string along with other details that are useful for running
+/// tests.
+#[derive(Debug)]
+pub struct DetailedFunction<'a> {
+    pub function: Function,
+    pub comments: Vec<Comment<'a>>,
+}
+
+/// A comment in a parsed function.
+///
+/// The comment belongs to the immediately preceeding entity, whether that is an EBB header, and
+/// instruction, or one of the preamble declarations.
+///
+/// Comments appearing inside the function but before the preamble, as well as comments appearing
+/// after the function are tagged as `AnyEntity::Function`.
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub struct Comment<'a> {
+    pub entity: AnyEntity,
+    pub text: &'a str,
+}