Remove unneeded assert

Author: takev

build/ucd_generator/generators.rs

@@ -68,7 +68,7 @@ pub fn generate_enum_table(code_dir : &std::path::Path, name : &str, enum_values
     write!(fd, "///\n")?;
     write!(fd, "/// # Returns\n")?;
     write!(fd, "/// A {} attribute of the Unicode code-point.\n", camel_name)?;
-    write!(fd, "pub const fn get_{}(code_point: char) -> {}\n", name, camel_name)?;
+    write!(fd, "#[must_use] pub const fn get_{}(code_point: char) -> {}\n", name, camel_name)?;
     write!(fd, "{{\n")?;
     write!(fd, "    const INDEX_MASK : usize = (1 << {}_INDEX_BITS) - 1;\n", upper_name)?;
     write!(fd, "    const COLUMN_MASK : usize = (1 << {}_COLUMN_BITS) - 1;\n\n", upper_name)?;
@@ -85,7 +85,7 @@ pub fn generate_enum_table(code_dir : &std::path::Path, name : &str, enum_values
     write!(fd, "    let index_bit_offset = index_offset % 8;\n")?;
     write!(fd, "    let mut index: usize = 0;\n")?;
     let index_bytes_to_read = (index_bits + 7) / 8 + 1;
-    for i in 0..index_bytes_to_read {
+    for i in (0..index_bytes_to_read).rev() {
         write!(fd, "    index |= ({}_INDEX[index_byte_offset + {}] as usize) << {};\n", upper_name, i, i * 8)?;
     }
     write!(fd, "    index >>= index_bit_offset;\n")?;
@@ -94,11 +94,10 @@ pub fn generate_enum_table(code_dir : &std::path::Path, name : &str, enum_values
     write!(fd, "    let column_offset = (index * {}_CHUNK_SIZE + code_point_lo) * {}_COLUMN_BITS;\n", upper_name, upper_name)?;
     write!(fd, "    let column_byte_offset = column_offset / 8;\n")?;
     write!(fd, "    let column_bit_offset = column_offset % 8;\n\n")?;
-    write!(fd, "    // Explicitly assert to replace a double bound check with single bound check.\n")?;
-    write!(fd, "    assert!(column_byte_offset + 1 < {}_COLUMN.len());\n", upper_name)?;
+
     write!(fd, "    let mut value: usize = 0;\n")?;
     let column_bytes_to_read = (column_bits + 7) / 8 + 1;
-    for i in 0..column_bytes_to_read {
+    for i in (0..column_bytes_to_read).rev() {
         write!(fd, "    value |= ({}_COLUMN[column_byte_offset + {}] as usize) << {};\n", upper_name, i, i * 8)?;
     }
     write!(fd, "    value >>= column_bit_offset;\n")?;

src/east_asian_width.rs

@@ -283,7 +283,7 @@ pub enum EastAsianWidth {
 ///
 /// # Returns
 /// A EastAsianWidth attribute of the Unicode code-point.
-pub const fn get_east_asian_width(code_point: char) -> EastAsianWidth
+#[must_use] pub const fn get_east_asian_width(code_point: char) -> EastAsianWidth
 {
     const INDEX_MASK : usize = (1 << EAST_ASIAN_WIDTH_INDEX_BITS) - 1;
     const COLUMN_MASK : usize = (1 << EAST_ASIAN_WIDTH_COLUMN_BITS) - 1;
@@ -299,20 +299,18 @@ pub const fn get_east_asian_width(code_point: char) -> EastAsianWidth
     let index_byte_offset = index_offset / 8;
     let index_bit_offset = index_offset % 8;
     let mut index: usize = 0;
-    index |= (EAST_ASIAN_WIDTH_INDEX[index_byte_offset + 0] as usize) << 0;
     index |= (EAST_ASIAN_WIDTH_INDEX[index_byte_offset + 1] as usize) << 8;
+    index |= (EAST_ASIAN_WIDTH_INDEX[index_byte_offset + 0] as usize) << 0;
     index >>= index_bit_offset;
     index &= INDEX_MASK;
 
     let column_offset = (index * EAST_ASIAN_WIDTH_CHUNK_SIZE + code_point_lo) * EAST_ASIAN_WIDTH_COLUMN_BITS;
     let column_byte_offset = column_offset / 8;
     let column_bit_offset = column_offset % 8;
 
-    // Explicitly assert to replace a double bound check with single bound check.
-    assert!(column_byte_offset + 1 < EAST_ASIAN_WIDTH_COLUMN.len());
     let mut value: usize = 0;
-    value |= (EAST_ASIAN_WIDTH_COLUMN[column_byte_offset + 0] as usize) << 0;
     value |= (EAST_ASIAN_WIDTH_COLUMN[column_byte_offset + 1] as usize) << 8;
+    value |= (EAST_ASIAN_WIDTH_COLUMN[column_byte_offset + 0] as usize) << 0;
     value >>= column_bit_offset;
     value &= COLUMN_MASK;
 

src/lib.rs

@@ -5,12 +5,24 @@ pub use east_asian_width::EastAsianWidth;
 pub use east_asian_width::get_east_asian_width;
 
 #[cfg(test)]
-mod tests {
+mod hikoru_ucdb {
     use super::*;
 
     #[test]
-    fn east_asian_width() {
+    fn east_asian_width()
+    {
         assert_eq!(get_east_asian_width('a'), EastAsianWidth::Na);
         assert_eq!(get_east_asian_width('あ'), EastAsianWidth::W);
     }
+
+    #[test]
+    fn east_asian_width_full_coverage()
+    {
+        for c in '\u{0000}'..='\u{d7ff}' {
+            let _ = get_east_asian_width(c);
+        }
+        for c in '\u{e000}'..='\u{10ffff}' {
+            let _ = get_east_asian_width(c);
+        }
+    }
 }