refactor(varcon): Move away from PHF

This is mostly to give implementation flexibility for changing out how
we store the data to reduce compilation memory usage.

This does have performance impact, jumping from ~220ns to ~320ns for a
dict lookup, according to our micro benchmarks.

Cargo.lock

@@ -1577,7 +1577,6 @@ name = "typos-vars"
 version = "0.5.0"
 dependencies = [
  "log",
- "phf",
  "unicase",
  "varcon-core",
 ]
@@ -1592,8 +1591,6 @@ dependencies = [
  "env_logger 0.7.1",
  "itertools 0.10.0",
  "log",
- "phf",
- "phf_codegen",
  "structopt",
  "typos",
  "unicase",

crates/typos-vars/Cargo.toml

@@ -15,7 +15,6 @@ azure-devops = { project = "crate-ci", pipeline = "typos" }
 codecov = { repository = "crate-ci/typos" }
 
 [dependencies]
-phf = { version = "0.8", features = ["unicase"] }
 unicase = "2.5"
 log = "0.4"
 varcon-core = { version = "^2.0", path = "../varcon-core", features = ["flags"] }

crates/typos-vars/codegen/Cargo.toml

@@ -15,8 +15,6 @@ azure-devops = { project = "crate-ci", pipeline = "typos" }
 codecov = { repository = "crate-ci/typos" }
 
 [dependencies]
-phf = { version = "0.8", features = ["unicase"] }
-phf_codegen = "0.8"
 varcon = { version = "^0.5", path = "../../varcon", features = ["flags"] }
 varcon-core = { version = "^2.0", path = "../../varcon-core", features = ["flags"] }
 typos = { version = "^0.6", path = "../../typos" }

crates/typos-vars/codegen/src/main.rs

@@ -26,9 +26,6 @@ fn generate_variations<W: std::io::Write>(file: &mut W) {
     writeln!(file, "#![allow(clippy::unreadable_literal)]",).unwrap();
     writeln!(file).unwrap();
 
-    writeln!(file, "use unicase::UniCase;").unwrap();
-    writeln!(file).unwrap();
-
     writeln!(file, "pub type Variants = &'static [&'static str];",).unwrap();
     writeln!(
         file,
@@ -82,12 +79,11 @@ fn generate_variations<W: std::io::Write>(file: &mut W) {
 
     writeln!(
         file,
-        "pub static VARS_DICTIONARY: phf::Map<unicase::UniCase<&'static str>, &'static [(u8, &VariantsMap)]> = "
+        "pub(crate) static VARS_DICTIONARY: &[(unicase::UniCase<&'static str>, &'static [(u8, &VariantsMap)])] = &["
     )
     .unwrap();
     let entry_sets = entry_sets(entries.iter());
     let mut referenced_symbols: HashSet<&str> = HashSet::new();
-    let mut builder = phf_codegen::Map::new();
     for (word, data) in entry_sets.iter() {
         if is_always_valid(data) {
             // No need to convert from current form to target form
@@ -95,15 +91,19 @@ fn generate_variations<W: std::io::Write>(file: &mut W) {
         }
         referenced_symbols.extend(data.iter().map(|(s, _)| s));
         let value = generate_link(&data);
-        builder.entry(unicase::UniCase::new(word), &value);
+        let word = unicase::UniCase::new(word);
+        let key = if word.is_ascii() {
+            format!("unicase::UniCase::ascii({:?})", word)
+        } else {
+            format!("unicase::UniCase::unicode({:?})", word)
+        };
+        writeln!(file, "  ({}, {}),", key, &value).unwrap();
         smallest = std::cmp::min(smallest, word.len());
         largest = std::cmp::max(largest, word.len());
 
         no_invalid &= !is_always_invalid(data);
     }
-    let codegenned = builder.build();
-    writeln!(file, "{}", codegenned).unwrap();
-    writeln!(file, ";").unwrap();
+    writeln!(file, "];").unwrap();
 
     writeln!(file).unwrap();
     writeln!(

crates/typos-vars/src/lib.rs

@@ -4,3 +4,10 @@ pub use crate::vars_codegen::*;
 
 pub use varcon_core::Category;
 pub use varcon_core::CategorySet;
+
+pub fn find(word: &'_ unicase::UniCase<&str>) -> Option<&'static [(u8, &'static VariantsMap)]> {
+    VARS_DICTIONARY
+        .binary_search_by_key(word, |(key, _)| *key)
+        .map(|i| VARS_DICTIONARY[i].1)
+        .ok()
+}

src/dict.rs

@@ -96,8 +96,8 @@ impl BuiltIn {
 
     fn correct_with_vars(&self, word: &str) -> Option<Status<'static>> {
         if self.is_vars_enabled() && typos_vars::WORD_RANGE.contains(&word.len()) {
-            map_lookup(&typos_vars::VARS_DICTIONARY, word)
-                .map(|variants| self.select_variant(variants))
+            let word_case = unicase::UniCase::new(word);
+            typos_vars::find(&word_case).map(|variants| self.select_variant(variants))
         } else {
             None
         }