feat(codegen): implement minify number from terser (#5929)

oxc-project · Sep 20, 2024 · d901772 · d901772
1 parent 6757c58
commit d901772
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Showing 3 changed files with 100 additions and 126 deletions.
diff --git a/crates/oxc_codegen/src/gen.rs b/crates/oxc_codegen/src/gen.rs
@@ -1110,16 +1110,17 @@ impl<'a> Gen for NumericLiteral<'a> {
     #[allow(clippy::cast_sign_loss, clippy::cast_possible_truncation)]
     fn gen(&self, p: &mut Codegen, _ctx: Context) {
         p.add_source_mapping(self.span.start);
-        if self.value != f64::INFINITY && (p.options.minify || self.raw.is_empty()) {
+        if !p.options.minify && !self.raw.is_empty() {
+            p.print_str(self.raw);
+            need_space_before_dot(self.raw, p);
+        } else if self.value != f64::INFINITY {
             p.print_space_before_identifier();
             let abs_value = self.value.abs();
-
             if self.value.is_sign_negative() {
                 p.print_space_before_operator(Operator::Unary(UnaryOperator::UnaryNegation));
                 p.print_str("-");
             }
-
-            let result = print_non_negative_float(abs_value, p);
+            let result = get_minified_number(abs_value);
             let bytes = result.as_str();
             p.print_str(bytes);
             need_space_before_dot(bytes, p);
@@ -1133,78 +1134,51 @@ impl<'a> Gen for NumericLiteral<'a> {
     }
 }
 
-// TODO: refactor this with less allocations
-// <https://github.com/evanw/esbuild/blob/360d47230813e67d0312ad754cad2b6ee09b151b/internal/js_printer/js_printer.go#L3472>
-#[allow(clippy::cast_possible_truncation, clippy::cast_sign_loss)]
-fn print_non_negative_float(value: f64, p: &Codegen) -> String {
+// https://github.com/terser/terser/blob/c5315c3fd6321d6b2e076af35a70ef532f498505/lib/output.js#L2418
+#[allow(clippy::cast_possible_truncation, clippy::cast_sign_loss, clippy::cast_possible_wrap)]
+fn get_minified_number(num: f64) -> String {
     use oxc_syntax::number::ToJsString;
-    if value < 1000.0 && value.fract() == 0.0 {
-        return value.to_js_string();
-    }
-    let mut result = format!("{value:e}");
-    let chars = result.as_bytes();
-    let len = chars.len();
-    let dot = chars.iter().position(|&c| c == b'.');
-    let u8_to_string = |num: &[u8]| {
-        // SAFETY: criteria of `from_utf8_unchecked`.are met.
-        unsafe { String::from_utf8_unchecked(num.to_vec()) }
-    };
-
-    if dot == Some(1) && chars[0] == b'0' {
-        // Strip off the leading zero when minifying
-        // "0.5" => ".5"
-        let stripped_result = &chars[1..];
-        // after stripping the leading zero, the after dot position will be start from 1
-        let after_dot = 1;
-
-        // Try using an exponent
-        // "0.001" => "1e-3"
-        if stripped_result[after_dot] == b'0' {
-            let mut i = after_dot + 1;
-            while stripped_result[i] == b'0' {
-                i += 1;
-            }
-            let remaining = &stripped_result[i..];
-            let exponent = format!("-{}", remaining.len() - after_dot + i);
-
-            // Only switch if it's actually shorter
-            if stripped_result.len() > remaining.len() + 1 + exponent.len() {
-                result = format!("{}e{}", u8_to_string(remaining), exponent);
-            } else {
-                result = u8_to_string(stripped_result);
-            }
-        } else {
-            result = u8_to_string(stripped_result);
-        }
-    } else if chars[len - 1] == b'0' {
-        // Simplify numbers ending with "0" by trying to use an exponent
-        // "1000" => "1e3"
-        let mut i = len - 1;
-        while i > 0 && chars[i - 1] == b'0' {
-            i -= 1;
-        }
-        let remaining = &chars[0..i];
-        let exponent = format!("{}", chars.len() - i);
+    if num < 1000.0 && num.fract() == 0.0 {
+        return num.to_js_string();
+    }
 
-        // Only switch if it's actually shorter
-        if chars.len() > remaining.len() + 1 + exponent.len() {
-            result = format!("{}e{}", u8_to_string(remaining), exponent);
-        } else {
-            result = u8_to_string(chars);
-        }
+    let mut s = num.to_js_string();
+
+    if s.starts_with("0.") {
+        s = s[1..].to_string();
     }
 
-    if p.options.minify && value.fract() == 0.0 {
-        let value = value as u64;
-        if (1_000_000_000_000..=0xFFFF_FFFF_FFFF_F800).contains(&value) {
-            let hex = format!("{value:#x}");
-            if hex.len() < result.len() {
-                result = hex;
-            }
+    s = s.cow_replacen("e+", "e", 1).to_string();
+
+    let mut candidates = vec![s.clone()];
+
+    if num.fract() == 0.0 {
+        candidates.push(format!("0x{:x}", num as u128));
+    }
+
+    if s.starts_with(".0") {
+        // create `1e-2`
+        if let Some((i, _)) = s[1..].bytes().enumerate().find(|(_, c)| *c != b'0') {
+            let len = i + 1; // `+1` to include the dot.
+            let digits = &s[len..];
+            candidates.push(format!("{digits}e-{}", digits.len() + len - 1));
+        }
+    } else if s.ends_with('0') {
+        // create 1e2
+        if let Some((len, _)) = s.bytes().rev().enumerate().find(|(_, c)| *c != b'0') {
+            candidates.push(format!("{}e{len}", &s[0..s.len() - len]));
         }
+    } else if let Some((integer, point, exponent)) =
+        s.split_once('.').and_then(|(a, b)| b.split_once('e').map(|e| (a, e.0, e.1)))
+    {
+        // `1.2e101` -> ("1", "2", "101")
+        candidates.push(format!(
+            "{integer}{point}e{}",
+            exponent.parse::<isize>().unwrap() - point.len() as isize
+        ));
     }
 
-    result
+    candidates.into_iter().min_by_key(String::len).unwrap()
 }
 
 impl<'a> Gen for BigIntLiteral<'a> {

diff --git a/crates/oxc_codegen/tests/integration/esbuild.rs b/crates/oxc_codegen/tests/integration/esbuild.rs
@@ -2,18 +2,18 @@
 
 use crate::tester::{test, test_minify};
 
+// NOTE: These values are aligned with terser, not esbuild.
 #[test]
-#[ignore]
 fn test_number() {
     // Check "1eN"
     test("x = 1e-100", "x = 1e-100;\n");
     test("x = 1e-4", "x = 1e-4;\n");
     test("x = 1e-3", "x = 1e-3;\n");
-    // test("x = 1e-2", "x = 0.01;\n");
-    // test("x = 1e-1", "x = 0.1;\n");
-    // test("x = 1e0", "x = 1;\n");
-    // test("x = 1e1", "x = 10;\n");
-    // test("x = 1e2", "x = 100;\n");
+    test("x = 1e-2", "x = 1e-2;\n");
+    test("x = 1e-1", "x = 1e-1;\n");
+    test("x = 1e0", "x = 1e0;\n");
+    test("x = 1e1", "x = 1e1;\n");
+    test("x = 1e2", "x = 1e2;\n");
     test("x = 1e3", "x = 1e3;\n");
     test("x = 1e4", "x = 1e4;\n");
     test("x = 1e100", "x = 1e100;\n");
@@ -28,22 +28,22 @@ fn test_number() {
     test_minify("x = 1e2", "x=100;");
     test_minify("x = 1e3", "x=1e3;");
     test_minify("x = 1e4", "x=1e4;");
-    // test_minify("x = 1e100", "x=1e100;");
+    test_minify("x = 1e100", "x=1e100;");
 
     // Check "12eN"
     test("x = 12e-100", "x = 12e-100;\n");
     test("x = 12e-5", "x = 12e-5;\n");
     test("x = 12e-4", "x = 12e-4;\n");
-    // test("x = 12e-3", "x = 0.012;\n");
-    // test("x = 12e-2", "x = 0.12;\n");
-    // test("x = 12e-1", "x = 1.2;\n");
-    // test("x = 12e0", "x = 12;\n");
-    // test("x = 12e1", "x = 120;\n");
-    // test("x = 12e2", "x = 1200;\n");
+    test("x = 12e-3", "x = 12e-3;\n");
+    test("x = 12e-2", "x = 12e-2;\n");
+    test("x = 12e-1", "x = 12e-1;\n");
+    test("x = 12e0", "x = 12e0;\n");
+    test("x = 12e1", "x = 12e1;\n");
+    test("x = 12e2", "x = 12e2;\n");
     test("x = 12e3", "x = 12e3;\n");
     test("x = 12e4", "x = 12e4;\n");
     test("x = 12e100", "x = 12e100;\n");
-    // test_minify("x = 12e-100", "x=12e-100;");
+    test_minify("x = 12e-100", "x=1.2e-99;");
     test_minify("x = 12e-6", "x=12e-6;");
     test_minify("x = 12e-5", "x=12e-5;");
     test_minify("x = 12e-4", "x=.0012;");
@@ -55,7 +55,7 @@ fn test_number() {
     test_minify("x = 12e2", "x=1200;");
     test_minify("x = 12e3", "x=12e3;");
     test_minify("x = 12e4", "x=12e4;");
-    // test_minify("x = 12e100", "x=12e100;");
+    test_minify("x = 12e100", "x=12e100;");
 
     // Check cases for "A.BeX" => "ABeY" simplification
     test("x = 123456789", "x = 123456789;\n");
@@ -66,11 +66,11 @@ fn test_number() {
     test("x = 10000123456789", "x = 10000123456789;\n");
     test("x = 100000123456789", "x = 100000123456789;\n");
     test("x = 1000000123456789", "x = 1000000123456789;\n");
-    // test("x = 10000000123456789", "x = 10000000123456788;\n");
-    // test("x = 100000000123456789", "x = 100000000123456780;\n");
-    // test("x = 1000000000123456789", "x = 1000000000123456800;\n");
-    // test("x = 10000000000123456789", "x = 10000000000123458e3;\n");
-    // test("x = 100000000000123456789", "x = 10000000000012345e4;\n");
+    test("x = 10000000123456789", "x = 10000000123456789;\n");
+    test("x = 100000000123456789", "x = 100000000123456789;\n");
+    test("x = 1000000000123456789", "x = 1000000000123456789;\n");
+    test("x = 10000000000123456789", "x = 10000000000123456789;\n");
+    test("x = 100000000000123456789", "x = 100000000000123456789;\n");
 
     // Check numbers around the ends of various integer ranges. These were
     // crashing in the WebAssembly build due to a bug in the Go runtime.
@@ -92,36 +92,36 @@ fn test_number() {
     test_minify("x = -0x1_0000_0001", "x=-4294967297;");
 
     // int64
-    test_minify("x = 0x7fff_ffff_ffff_fdff", "x=9223372036854775e3;");
-    test_minify("x = 0x8000_0000_0000_0000", "x=9223372036854776e3;");
-    test_minify("x = 0x8000_0000_0000_3000", "x=9223372036854788e3;");
-    test_minify("x = -0x7fff_ffff_ffff_fdff", "x=-9223372036854775e3;");
-    test_minify("x = -0x8000_0000_0000_0000", "x=-9223372036854776e3;");
-    test_minify("x = -0x8000_0000_0000_3000", "x=-9223372036854788e3;");
+    test_minify("x = 0x7fff_ffff_ffff_fdff", "x=0x7ffffffffffffc00;");
+    test_minify("x = 0x8000_0000_0000_0000", "x=0x8000000000000000;");
+    test_minify("x = 0x8000_0000_0000_3000", "x=0x8000000000003000;");
+    test_minify("x = -0x7fff_ffff_ffff_fdff", "x=-0x7ffffffffffffc00;");
+    test_minify("x = -0x8000_0000_0000_0000", "x=-0x8000000000000000;");
+    test_minify("x = -0x8000_0000_0000_3000", "x=-0x8000000000003000;");
 
     // uint64
-    test_minify("x = 0xffff_ffff_ffff_fbff", "x=1844674407370955e4;");
-    test_minify("x = 0x1_0000_0000_0000_0000", "x=18446744073709552e3;");
-    test_minify("x = 0x1_0000_0000_0000_1000", "x=18446744073709556e3;");
-    test_minify("x = -0xffff_ffff_ffff_fbff", "x=-1844674407370955e4;");
-    test_minify("x = -0x1_0000_0000_0000_0000", "x=-18446744073709552e3;");
-    test_minify("x = -0x1_0000_0000_0000_1000", "x=-18446744073709556e3;");
+    test_minify("x = 0xffff_ffff_ffff_fbff", "x=0xfffffffffffff800;");
+    test_minify("x = 0x1_0000_0000_0000_0000", "x=0x10000000000000000;");
+    test_minify("x = 0x1_0000_0000_0000_1000", "x=0x10000000000001000;");
+    test_minify("x = -0xffff_ffff_ffff_fbff", "x=-0xfffffffffffff800;");
+    test_minify("x = -0x1_0000_0000_0000_0000", "x=-0x10000000000000000;");
+    test_minify("x = -0x1_0000_0000_0000_1000", "x=-0x10000000000001000;");
 
     // Check the hex vs. decimal decision boundary when minifying
-    // test("x = 999999999999", "x = 999999999999;\n");
-    // test("x = 1000000000001", "x = 1000000000001;\n");
-    // test("x = 0x0FFF_FFFF_FFFF_FF80", "x = 1152921504606846800;\n");
-    // test("x = 0x1000_0000_0000_0000", "x = 1152921504606847e3;\n");
-    // test("x = 0xFFFF_FFFF_FFFF_F000", "x = 18446744073709548e3;\n");
-    // test("x = 0xFFFF_FFFF_FFFF_F800", "x = 1844674407370955e4;\n");
-    // test("x = 0xFFFF_FFFF_FFFF_FFFF", "x = 18446744073709552e3;\n");
-    // test_minify("x = 999999999999", "x=999999999999;");
-    // test_minify("x = 1000000000001", "x=0xe8d4a51001;");
-    // test_minify("x = 0x0FFF_FFFF_FFFF_FF80", "x=0xfffffffffffff80;");
-    // test_minify("x = 0x1000_0000_0000_0000", "x=1152921504606847e3;");
-    // test_minify("x = 0xFFFF_FFFF_FFFF_F000", "x=0xfffffffffffff000;");
-    // test_minify("x = 0xFFFF_FFFF_FFFF_F800", "x=1844674407370955e4;");
-    // test_minify("x = 0xFFFF_FFFF_FFFF_FFFF", "x=18446744073709552e3;");
+    test("x = 999999999999", "x = 999999999999;\n");
+    test("x = 1000000000001", "x = 1000000000001;\n");
+    test("x = 0x0FFF_FFFF_FFFF_FF80", "x = 0x0FFF_FFFF_FFFF_FF80;\n");
+    test("x = 0x1000_0000_0000_0000", "x = 0x1000_0000_0000_0000;\n");
+    test("x = 0xFFFF_FFFF_FFFF_F000", "x = 0xFFFF_FFFF_FFFF_F000;\n");
+    test("x = 0xFFFF_FFFF_FFFF_F800", "x = 0xFFFF_FFFF_FFFF_F800;\n");
+    test("x = 0xFFFF_FFFF_FFFF_FFFF", "x = 0xFFFF_FFFF_FFFF_FFFF;\n");
+    test_minify("x = 999999999999", "x=999999999999;");
+    test_minify("x = 1000000000001", "x=0xe8d4a51001;");
+    test_minify("x = 0x0FFF_FFFF_FFFF_FF80", "x=0xfffffffffffff80;");
+    test_minify("x = 0x1000_0000_0000_0000", "x=0x1000000000000000;");
+    test_minify("x = 0xFFFF_FFFF_FFFF_F000", "x=0xfffffffffffff000;");
+    test_minify("x = 0xFFFF_FFFF_FFFF_F800", "x=0xfffffffffffff800;");
+    test_minify("x = 0xFFFF_FFFF_FFFF_FFFF", "x=0x10000000000000000;");
 
     // Check printing a space in between a number and a subsequent "."
     test_minify("x = 0.0001 .y", "x=1e-4.y;");

diff --git a/tasks/minsize/minsize.snap b/tasks/minsize/minsize.snap
@@ -1,26 +1,26 @@
 Original   | Minified   | esbuild    | Gzip       | esbuild   
 
-72.14 kB   | 24.37 kB   | 23.70 kB   | 8.73 kB    | 8.54 kB    | react.development.js
+72.14 kB   | 24.32 kB   | 23.70 kB   | 8.71 kB    | 8.54 kB    | react.development.js
 
-173.90 kB  | 61.83 kB   | 59.82 kB   | 19.59 kB   | 19.33 kB   | moment.js 
+173.90 kB  | 61.79 kB   | 59.82 kB   | 19.57 kB   | 19.33 kB   | moment.js 
 
-287.63 kB  | 92.93 kB   | 90.07 kB   | 32.35 kB   | 31.95 kB   | jquery.js 
+287.63 kB  | 92.91 kB   | 90.07 kB   | 32.33 kB   | 31.95 kB   | jquery.js 
 
 342.15 kB  | 122.97 kB  | 118.14 kB  | 45.05 kB   | 44.37 kB   | vue.js    
 
-544.10 kB  | 73.57 kB   | 72.48 kB   | 26.14 kB   | 26.20 kB   | lodash.js 
+544.10 kB  | 73.57 kB   | 72.48 kB   | 26.15 kB   | 26.20 kB   | lodash.js 
 
-555.77 kB  | 275.81 kB  | 270.13 kB  | 91.66 kB   | 90.80 kB   | d3.js     
+555.77 kB  | 274.81 kB  | 270.13 kB  | 91.40 kB   | 90.80 kB   | d3.js     
 
-1.01 MB    | 471.78 kB  | 458.89 kB  | 127.61 kB  | 126.71 kB  | bundle.min.js
+1.01 MB    | 471.70 kB  | 458.89 kB  | 127.56 kB  | 126.71 kB  | bundle.min.js
 
-1.25 MB    | 676.14 kB  | 646.76 kB  | 167.18 kB  | 163.73 kB  | three.js  
+1.25 MB    | 673.75 kB  | 646.76 kB  | 166.76 kB  | 163.73 kB  | three.js  
 
-2.14 MB    | 751.46 kB  | 724.14 kB  | 182.74 kB  | 181.07 kB  | victory.js
+2.14 MB    | 743.40 kB  | 724.14 kB  | 181.95 kB  | 181.07 kB  | victory.js
 
-3.20 MB    | 1.03 MB    | 1.01 MB    | 332.60 kB  | 331.56 kB  | echarts.js
+3.20 MB    | 1.03 MB    | 1.01 MB    | 332.45 kB  | 331.56 kB  | echarts.js
 
-6.69 MB    | 2.42 MB    | 2.31 MB    | 503.22 kB  | 488.28 kB  | antd.js   
+6.69 MB    | 2.42 MB    | 2.31 MB    | 503.16 kB  | 488.28 kB  | antd.js   
 
-10.95 MB   | 3.60 MB    | 3.49 MB    | 915.21 kB  | 915.50 kB  | typescript.js
+10.95 MB   | 3.57 MB    | 3.49 MB    | 912.37 kB  | 915.50 kB  | typescript.js