[tests] Add conformance tests using BidiTest.txt

tests/conformance_tests.rs

@@ -0,0 +1,198 @@
+// Copyright 2014 The html5ever Project Developers. See the
+// COPYRIGHT file at the top-level directory of this distribution.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![cfg(test)]
+
+extern crate unicode_bidi;
+
+use std::fs::File;
+use std::io::{BufRead, BufReader};
+use std::path::Path;
+
+use unicode_bidi::{BidiInfo, format_chars, Level, process_text};
+
+const TEST_DATA_DIR: &str = "tests/data";
+const BASE_TEST_FILE_NAME: &str = "BidiTest.txt";
+//const CHAR_TEST_FILE_NAME: &str = "BidiCharacterTest.txt";
+
+fn open_test_file(filename: &str) -> File {
+    let path = Path::new(TEST_DATA_DIR).join(filename);
+    return File::open(&path).unwrap();
+}
+
+#[derive(Debug)]
+struct Fail {
+    pub levels: Vec<String>,
+    pub ordering: Vec<String>,
+    pub input: Vec<String>,
+    pub input_chars: String,
+    pub para_level: Option<Level>,
+}
+
+#[test]
+#[should_panic(expected = "60494 test cases failed! (196253 passed)")]
+fn base_tests() {
+    let file = open_test_file(BASE_TEST_FILE_NAME);
+    let read = BufReader::new(file);
+
+    // State
+    let mut passed_num: i32 = 0;
+    let mut fails: Vec<Fail> = Vec::new();
+    let mut set_levels: Vec<String> = Vec::new();
+    let mut set_ordering: Vec<String> = Vec::new();
+    //let mut line_num = 0;
+
+    for line in read.lines().map(|x| x.unwrap()) {
+        //line_num += 1;
+        let line = line.trim();
+
+        // Empty and comment lines
+        if line.is_empty() || line.starts_with('#') {
+            // Ignore
+            continue;
+        }
+
+        // State setting lines
+        if line.starts_with('@') {
+            let tokens: Vec<String> = line.split_whitespace().map(|x| x.to_owned()).collect();
+            let (setting, values) = (tokens[0].as_ref(), tokens[1..].to_vec());
+            match setting {
+                "@Levels:" => {
+                    set_levels = values.to_owned();
+                }
+                "@Reorder:" => {
+                    set_ordering = values.to_owned();
+                }
+                _ => {
+                    // Ignore, to allow some degree of forward compatibility
+                }
+            }
+            continue;
+        }
+
+        // Data lines
+        {
+            // Levels and ordering need to be set before any data line
+            assert!(set_levels.len() > 0);
+            assert!(set_ordering.len() <= set_levels.len());
+
+            let pieces: Vec<&str> = line.split(';').collect();
+            let input: Vec<&str> = pieces[0].split_whitespace().collect();
+            let bitset: u8 = pieces[1].trim().parse().unwrap();
+            assert!(input.len() > 0);
+            assert!(bitset > 0);
+
+            let input_chars = get_sample_string_from_bidi_classes(input.to_owned());
+
+            for para_level in gen_para_levels(bitset) {
+                let bidi_info = process_text(&input_chars, para_level);
+
+                // Levels
+                let exp_levels: Vec<&str> = set_levels.iter().map(|x| x.as_ref()).collect();
+                let levels = gen_levels_list_from_bidi_info(&input_chars, &bidi_info);
+                if levels != exp_levels {
+                    fails.push(
+                        Fail {
+                            levels: set_levels.to_owned(),
+                            ordering: set_ordering.to_owned(),
+                            input: input.iter().map(|x| x.to_string()).collect(),
+                            input_chars: input_chars.to_owned(),
+                            para_level,
+                        },
+                    );
+                } else {
+                    passed_num += 1;
+                }
+
+                // Ordering
+                // TODO: Add reorder map to API output and test the map here
+            }
+        }
+    }
+
+    if fails.len() > 0 {
+        // TODO: Show a list of failed cases when the number is less than 1K
+        panic!(
+            "{} test cases failed! ({} passed) {{\n\
+            \n\
+            0: {:?}\n\
+            \n\
+            ...\n\
+            \n\
+            {}: {:?}\n\
+            \n\
+            }}",
+            fails.len(),
+            passed_num,
+            fails[0],
+            fails.len() - 1,
+            fails[fails.len() - 1],
+        );
+    }
+}
+
+fn gen_para_levels(bitset: u8) -> Vec<Option<Level>> {
+    /// Values: auto-LTR, LTR, RTL
+    // TODO: Support auto-RTL
+    // FIXME: Convert back to `const` when `const fn` becomes possible
+    let para_level_values: &[Option<Level>] = &[None, Some(Level::ltr()), Some(Level::rtl())];
+    assert!(bitset < (1 << para_level_values.len()));
+
+    (0..3)
+        .filter(|bit| bitset & (1u8 << bit) == 1)
+        .map(|idx| para_level_values[idx])
+        .collect()
+}
+
+/// We need to collaps levels to one-per-character from one-per-byte format.
+///
+/// TODO: Move to impl BidiInfo as pub api
+fn gen_levels_list_from_bidi_info(input_chars: &str, bidi_info: &BidiInfo) -> Vec<Level> {
+    input_chars
+        .char_indices()
+        .map(|(i, _)| bidi_info.levels[i])
+        .collect()
+}
+
+fn get_sample_string_from_bidi_classes(class_names: Vec<&str>) -> String {
+    class_names
+        .iter()
+        .map(|class_name| gen_char_from_bidi_class(class_name))
+        .collect()
+}
+
+/// TODO: Auto-gen in tables.rs ?
+fn gen_char_from_bidi_class(class_name: &str) -> char {
+    match class_name {
+        "AL" => '\u{060b}',
+        "AN" => '\u{0605}',
+        "B" => '\u{000a}',
+        "BN" => '\u{0000}',
+        "CS" => '\u{002c}',
+        "EN" => '\u{0039}',
+        "ES" => '\u{002b}',
+        "ET" => '\u{0023}',
+        "FSI" => format_chars::FSI,
+        "L" => '\u{0041}',
+        "LRE" => format_chars::LRE,
+        "LRI" => format_chars::LRI,
+        "LRO" => format_chars::LRO,
+        "NSM" => '\u{0300}',
+        "ON" => '\u{0021}',
+        "PDF" => format_chars::PDF,
+        "PDI" => format_chars::PDI,
+        "R" => '\u{0590}',
+        "RLE" => format_chars::RLE,
+        "RLI" => format_chars::RLI,
+        "RLO" => format_chars::RLO,
+        "S" => '\u{0009}',
+        "WS" => '\u{000c}',
+        &_ => panic!("Invalid Bidi_Class name: {}", class_name),
+    }
+}