fix(es/minifier): Fix handling of template literals (#4563)

crates/swc_ecma_minifier/src/compress/pure/misc.rs

@@ -7,7 +7,7 @@ use swc_ecma_utils::ident::IdentLike;
 
 use super::Pure;
 use crate::compress::{
-    pure::strings::convert_str_value_to_tpl_cooked,
+    pure::strings::{convert_str_value_to_tpl_cooked, convert_str_value_to_tpl_raw},
     util::{is_global_var, is_pure_undefined},
 };
 
@@ -404,7 +404,7 @@ impl Pure<'_> {
                 }
                 Expr::Lit(Lit::Str(s)) => {
                     cur_cooked.push_str(&convert_str_value_to_tpl_cooked(&s.value));
-                    cur_raw.push_str(&s.value);
+                    cur_raw.push_str(&convert_str_value_to_tpl_raw(&s.value));
                 }
                 _ => {
                     unreachable!()

crates/swc_ecma_minifier/src/compress/pure/strings.rs

@@ -1,4 +1,4 @@
-use std::mem::take;
+use std::{borrow::Cow, mem::take};
 
 use swc_atoms::{js_word, JsWord};
 use swc_common::{util::take::Take, DUMMY_SP};
@@ -196,6 +196,7 @@ impl Pure<'_> {
                     '\n' | '\r' => self.config.force_str_for_tpl,
                     _ => false,
                 }) && (self.config.force_str_for_tpl
+                    || c.contains("\\`")
                     || (!c.contains("\\n") && !c.contains("\\r")))
                     && !c.contains("\\0")
                     && !c.contains("\\x")
@@ -238,26 +239,31 @@ impl Pure<'_> {
         let mut quasis = vec![];
         let mut exprs = vec![];
         let mut cur_raw = String::new();
+        let mut cur_cooked = String::new();
 
         for i in 0..(tpl.exprs.len() + tpl.quasis.len()) {
             if i % 2 == 0 {
                 let i = i / 2;
                 let q = tpl.quasis[i].take();
 
                 cur_raw.push_str(&q.raw);
+                if let Some(cooked) = q.cooked {
+                    cur_cooked.push_str(&cooked);
+                }
             } else {
                 let i = i / 2;
                 let e = tpl.exprs[i].take();
 
                 match *e {
                     Expr::Lit(Lit::Str(s)) => {
-                        cur_raw.push_str(&s.value);
+                        cur_raw.push_str(&convert_str_value_to_tpl_raw(&s.value));
+                        cur_cooked.push_str(&convert_str_value_to_tpl_cooked(&s.value));
                     }
                     _ => {
                         quasis.push(TplElement {
                             span: DUMMY_SP,
                             tail: true,
-                            cooked: None,
+                            cooked: Some(JsWord::from(&*cur_cooked)),
                             raw: take(&mut cur_raw).into(),
                         });
 
@@ -267,6 +273,8 @@ impl Pure<'_> {
             }
         }
 
+        report_change!("compressing template literals");
+
         quasis.push(TplElement {
             span: DUMMY_SP,
             tail: true,
@@ -294,11 +302,13 @@ impl Pure<'_> {
                     );
 
                     if let Some(cooked) = &mut l_last.cooked {
-                        *cooked = format!("{}{}", cooked, rs.value.replace('\\', "\\\\")).into()
+                        *cooked =
+                            format!("{}{}", cooked, convert_str_value_to_tpl_cooked(&rs.value))
+                                .into();
                     }
 
                     let new: JsWord =
-                        format!("{}{}", l_last.raw, rs.value.replace('\\', "\\\\")).into();
+                        format!("{}{}", l_last.raw, convert_str_value_to_tpl_raw(&rs.value)).into();
                     l_last.raw = new;
 
                     r.take();
@@ -316,11 +326,14 @@ impl Pure<'_> {
                     );
 
                     if let Some(cooked) = &mut r_first.cooked {
-                        *cooked = format!("{}{}", ls.value.replace('\\', "\\\\"), cooked).into()
+                        *cooked =
+                            format!("{}{}", convert_str_value_to_tpl_cooked(&ls.value), cooked)
+                                .into()
                     }
 
                     let new: JsWord =
-                        format!("{}{}", ls.value.replace('\\', "\\\\"), r_first.raw).into();
+                        format!("{}{}", convert_str_value_to_tpl_raw(&ls.value), r_first.raw)
+                            .into();
                     r_first.raw = new;
 
                     l.take();
@@ -449,12 +462,20 @@ impl Pure<'_> {
     }
 }
 
-pub(super) fn convert_str_value_to_tpl_cooked(value: &JsWord) -> JsWord {
+pub(super) fn convert_str_value_to_tpl_cooked(value: &JsWord) -> Cow<str> {
     value
+        .replace('\\', "\\\\")
+        .replace('`', "\\`")
+        .replace('$', "\\$")
+        .into()
+}
+
+pub(super) fn convert_str_value_to_tpl_raw(value: &JsWord) -> Cow<str> {
+    value
+        .replace('\\', "\\\\")
         .replace('`', "\\`")
         .replace('$', "\\$")
         .replace('\n', "\\n")
         .replace('\r', "\\r")
-        .replace('\\', "\\\\")
         .into()
 }

crates/swc_ecma_minifier/tests/TODO.txt

@@ -143,5 +143,3 @@ sequences/delete_seq_5/input.js
 sequences/for_sequences/input.js
 sequences/issue_1758/input.js
 sequences/lift_sequences_5/input.js
-template_string/special_chars_in_string/input.js
-transform/if_else_empty/input.js

crates/swc_ecma_minifier/tests/golden.txt

@@ -1338,6 +1338,7 @@ template_string/semicolons/input.js
 template_string/sequence_1/input.js
 template_string/sequence_2/input.js
 template_string/simple_string/input.js
+template_string/special_chars_in_string/input.js
 template_string/tagged_call_with_invalid_escape/input.js
 template_string/tagged_call_with_invalid_escape_2/input.js
 template_string/tagged_template_function_inline_1/input.js
@@ -1368,6 +1369,7 @@ template_string/template_with_newline/input.js
 transform/booleans_evaluate/input.js
 transform/booleans_global_defs/input.js
 transform/condition_evaluate/input.js
+transform/if_else_empty/input.js
 transform/if_return/input.js
 transform/while_if_break/input.js
 try_catch/broken_safari_catch_scope/input.js

crates/swc_ecma_minifier/tests/terser/compress/transform/if_else_empty/output.js

@@ -0,0 +1 @@
+a;

crates/swc_html_parser/tests/fixture.rs

@@ -1,5 +1,7 @@
 #![deny(warnings)]
 #![allow(clippy::needless_update)]
+#![allow(clippy::redundant_clone)]
+#![allow(clippy::while_let_on_iterator)]
 
 use std::{fs, mem::take, path::PathBuf};
 
@@ -788,19 +790,19 @@ impl VisitMut for DomVisualizer<'_> {
         document_type.push_str("<!DOCTYPE ");
 
         if let Some(name) = &n.name {
-            document_type.push_str(&name);
+            document_type.push_str(name);
         }
 
         if let Some(public_id) = &n.public_id {
             document_type.push(' ');
             document_type.push('"');
-            document_type.push_str(&public_id);
+            document_type.push_str(public_id);
             document_type.push('"');
 
             if let Some(system_id) = &n.system_id {
                 document_type.push(' ');
                 document_type.push('"');
-                document_type.push_str(&system_id);
+                document_type.push_str(system_id);
                 document_type.push('"');
             } else {
                 document_type.push(' ');
@@ -813,7 +815,7 @@ impl VisitMut for DomVisualizer<'_> {
             document_type.push('"');
             document_type.push(' ');
             document_type.push('"');
-            document_type.push_str(&system_id);
+            document_type.push_str(system_id);
             document_type.push('"');
         }
 
@@ -865,7 +867,7 @@ impl VisitMut for DomVisualizer<'_> {
         attribute.push_str(&self.get_ident());
 
         if let Some(prefix) = &n.prefix {
-            attribute.push_str(&prefix);
+            attribute.push_str(prefix);
             attribute.push(' ');
         }
 
@@ -874,7 +876,7 @@ impl VisitMut for DomVisualizer<'_> {
         attribute.push('"');
 
         if let Some(value) = &n.value {
-            attribute.push_str(&value);
+            attribute.push_str(value);
         }
 
         attribute.push('"');
@@ -961,9 +963,9 @@ fn html5lib_test_tree_construction(input: PathBuf) {
                 .find("#errors\n")
                 .expect("failed to get errors in test");
             let mut data = &test[data_start..data_end];
-            if data.ends_with("\n") {
+            if data.ends_with('\n') {
                 data = data
-                    .strip_suffix("\n")
+                    .strip_suffix('\n')
                     .expect("failed to strip last line in test");
             }
 

crates/swc_plugin_proxy/src/source_map/plugin_source_map_proxy.rs

@@ -1,3 +1,4 @@
+#![allow(unused_variables)]
 #[cfg(feature = "plugin-mode")]
 use swc_common::{source_map::FileLinesResult, BytePos, FileName, Loc, SourceMapper, Span};