add a mechanism for autogenerating test fixtures

1 files changed, 99 insertions, 0 deletions

diff --git a/examples/generate_fixture.rs b/examples/generate_fixture.rs
new file mode 100644
index 0000000..a411e8b
--- /dev/null
+++ b/examples/generate_fixture.rs
@@ -0,0 +1,99 @@
+use std::convert::TryFrom as _;
+use std::io::BufRead as _;
+use std::io::Write as _;
+
+#[path = "../tests/helpers/mod.rs"]
+mod helpers;
+
+fn main() {
+    let name = std::env::args().nth(1).unwrap();
+    let _ = std::fs::remove_dir_all(format!("tests/data/fixtures/{}", name));
+    std::fs::create_dir_all(format!("tests/data/fixtures/{}", name)).unwrap();
+
+    let inputs =
+        std::fs::File::open(format!("tests/data/fixtures/{}.in", name))
+            .unwrap();
+    let inputs = std::io::BufReader::new(inputs);
+
+    let mut i = 1;
+    let mut prev_input = vec![];
+    for line in inputs.lines() {
+        let line = line.unwrap();
+
+        let input = unhex(line.as_bytes());
+        let mut input_file = std::fs::File::create(format!(
+            "tests/data/fixtures/{}/{}.typescript",
+            name, i
+        ))
+        .unwrap();
+        input_file.write_all(&input).unwrap();
+
+        prev_input.extend(input);
+        let mut term = vt100::Parser::default();
+        term.process(&prev_input);
+        let screen = helpers::FixtureScreen::from_screen(term.screen());
+
+        let output_file = std::fs::File::create(format!(
+            "tests/data/fixtures/{}/{}.json",
+            name, i
+        ))
+        .unwrap();
+        serde_json::to_writer_pretty(output_file, &screen).unwrap();
+
+        i += 1;
+    }
+}
+
+fn unhex(s: &[u8]) -> Vec<u8> {
+    let mut ret = vec![];
+    let mut i = 0;
+    while i < s.len() {
+        if s[i] == b'\\' {
+            match s[i + 1] {
+                b'x' => {
+                    let upper = s[i + 2];
+                    let lower = s[i + 3];
+                    ret.push(helpers::hex(upper, lower).unwrap());
+                    i += 4;
+                }
+                b'u' => {
+                    assert_eq!(s[i + 2], b'{');
+                    let mut digits = vec![];
+                    let mut j = i + 3;
+                    while s[j] != b'}' {
+                        digits.push(s[j]);
+                        j += 1;
+                    }
+                    let digits: Vec<_> = digits
+                        .iter()
+                        .copied()
+                        .skip_while(|x| x == &b'0')
+                        .collect();
+                    let digits = String::from_utf8(digits).unwrap();
+                    let codepoint = u32::from_str_radix(&digits, 16).unwrap();
+                    let c = char::try_from(codepoint).unwrap();
+                    let mut bytes = [0; 4];
+                    ret.extend(c.encode_utf8(&mut bytes).bytes());
+                    i = j + 1;
+                }
+                b'r' => {
+                    ret.push(0x0d);
+                    i += 2;
+                }
+                b'n' => {
+                    ret.push(0x0a);
+                    i += 2;
+                }
+                b't' => {
+                    ret.push(0x09);
+                    i += 2;
+                }
+                _ => panic!("invalid escape"),
+            }
+        } else {
+            ret.push(s[i]);
+            i += 1;
+        }
+    }
+    ret
+}