1
0

Tweak the chunk disassembly

This commit is contained in:
Jeff 2024-09-14 13:59:11 -04:00
parent 2ad3440097
commit 8534f18c9a

View File

@ -287,7 +287,7 @@ impl<'a> ChunkDisassembler<'a> {
/// The default width of the disassembly output. To correctly align the output, this should be
/// set to the width of the longest line that the disassembler is guaranteed to produce.
const DEFAULT_WIDTH: usize = Self::INSTRUCTION_HEADER[3].len() + 1;
const DEFAULT_WIDTH: usize = Self::INSTRUCTION_HEADER[4].len() + 1;
pub fn new(name: &'a str, chunk: &'a Chunk) -> Self {
Self {
@ -308,11 +308,12 @@ impl<'a> ChunkDisassembler<'a> {
}
};
let name_line = style(center(&format!("{}", self.name)));
let mut disassembled = String::with_capacity(self.predict_capacity());
let mut disassembled = String::with_capacity(self.predict_length());
println!("capactity: {}", disassembled.capacity());
let name_line = style(center(self.name));
disassembled.push_str(&name_line);
for line in Self::INSTRUCTION_HEADER {
@ -345,7 +346,7 @@ impl<'a> ChunkDisassembler<'a> {
let value_display = value_option
.as_ref()
.map(|value| value.to_string())
.unwrap_or_else(|| "EMPTY".to_string());
.unwrap_or_else(|| "empty".to_string());
let constant_display = format!("{index:<5} {value_kind_display:<5} {value_display:<5}");
disassembled.push_str(&center(&constant_display));
@ -367,7 +368,7 @@ impl<'a> ChunkDisassembler<'a> {
let register_display = register_index
.as_ref()
.map(|value| value.to_string())
.unwrap_or_else(|| "EMPTY".to_string());
.unwrap_or_else(|| "empty".to_string());
let identifier_display = identifier.as_str();
let local_display =
format!("{index:<5} {identifier_display:<10} {depth:<5} {register_display:<8}");
@ -400,19 +401,20 @@ impl<'a> ChunkDisassembler<'a> {
/// - Get the number of dynamic lines, i.e. lines that are generated from the chunk
/// - Add 1 to the width to account for the newline character
/// - Multiply the total number of lines by the width of the disassembly output
fn predict_capacity(&self) -> usize {
const EXTRA_LINES: usize = 1;
///
/// The result is accurate only if the output is not styled. Otherwise the extra bytes added by
/// the ANSI escape codes will make the result too low. It still works as a lower bound in that
/// case.
fn predict_length(&self) -> usize {
const EXTRA_LINES: usize = 1; // There is one empty line after the name of the chunk
let chunk_header_line_count = 3; // self.chunk_header().len() is hard-coded to 3
let static_line_count = chunk_header_line_count
+ Self::INSTRUCTION_HEADER.len()
+ Self::CONSTANT_HEADER.len()
+ Self::LOCAL_HEADER.len();
let static_line_count =
Self::INSTRUCTION_HEADER.len() + Self::CONSTANT_HEADER.len() + Self::LOCAL_HEADER.len();
let dynamic_line_count =
self.chunk.instructions.len() + self.chunk.constants.len() + self.chunk.locals.len();
let total_line_count = static_line_count + dynamic_line_count + EXTRA_LINES;
total_line_count * (self.width)
total_line_count * (self.width + 1)
}
}