fix(es/minifier): Fix a bug in tpl string <-> string logic (#8510)

**Related issue:**

 - Closes #8496

crates/swc/tests/fixture/issues-8xxx/8496/input/.swcrc

@@ -0,0 +1,70 @@
+{
+    "jsc": {
+        "parser": {
+            "syntax": "ecmascript",
+            "jsx": false
+        },
+        "loose": true,
+        "minify": {
+            "mangle": false,
+            "compress": {
+                "arguments": false,
+                "arrows": true,
+                "booleans": true,
+                "booleans_as_integers": false,
+                "collapse_vars": true,
+                "comparisons": true,
+                "computed_props": true,
+                "conditionals": true,
+                "dead_code": true,
+                "directives": true,
+                "drop_console": false,
+                "drop_debugger": true,
+                "evaluate": true,
+                "expression": false,
+                "hoist_funs": false,
+                "hoist_props": true,
+                "hoist_vars": false,
+                "if_return": true,
+                "join_vars": true,
+                "keep_classnames": false,
+                "keep_fargs": true,
+                "keep_fnames": false,
+                "keep_infinity": false,
+                "loops": true,
+                "negate_iife": true,
+                "properties": true,
+                "reduce_funcs": false,
+                "reduce_vars": false,
+                "side_effects": true,
+                "switches": true,
+                "typeofs": true,
+                "unsafe": false,
+                "unsafe_arrows": false,
+                "unsafe_comps": false,
+                "unsafe_Function": false,
+                "unsafe_math": false,
+                "unsafe_symbols": false,
+                "unsafe_methods": false,
+                "unsafe_proto": false,
+                "unsafe_regexp": false,
+                "unsafe_undefined": false,
+                "unused": true,
+                "const_to_let": true,
+                "pristine_globals": true
+            }
+        }
+    },
+    "module": {
+        "type": "es6"
+    },
+    "minify": true,
+    "isModule": true,
+    "env": {
+        "targets": {
+            "chrome": 109
+        },
+        "coreJs": "3.21",
+        "mode": "usage"
+    }
+}

crates/swc/tests/fixture/issues-8xxx/8496/input/1.js

@@ -0,0 +1,3 @@
+export const strWithDollar = `$login`;
+
+export const use = `${strWithDollar}`; // expected: "$login" without \\

crates/swc/tests/fixture/issues-8xxx/8496/input/2.js

@@ -0,0 +1,3 @@
+export const strWithDollar = `$login`;
+
+export const use = `${strWithDollar}${1}`; // expected: "$login" without \\

crates/swc/tests/fixture/issues-8xxx/8496/input/3.js

@@ -0,0 +1,3 @@
+export const strWithDollar = `$login`;
+
+export const use = `${1}${strWithDollar}`; // expected: "$login" without \\

crates/swc/tests/fixture/issues-8xxx/8496/input/4.js

@@ -0,0 +1,3 @@
+export const strWithDollar = `$login`;
+
+export const use = `asd${strWithDollar}`; // expected: "$login" without \\

crates/swc/tests/fixture/issues-8xxx/8496/input/5.js

@@ -0,0 +1,3 @@
+export const strWithDollar = `$login`;
+
+export const use = `$${strWithDollar}`; // expected: "$login" without \\

crates/swc/tests/fixture/issues-8xxx/8496/input/6.js

@@ -0,0 +1,3 @@
+export const strWithDollar = `$login`;
+
+export const use = `{${strWithDollar}`; // expected: "$login" without \\

crates/swc/tests/fixture/issues-8xxx/8496/input/7.js

@@ -0,0 +1,3 @@
+export const strWithDollar = `$login`;
+
+export const use = `\{${strWithDollar}`; // expected: "$login" without \\

crates/swc/tests/fixture/issues-8xxx/8496/input/8.js

@@ -0,0 +1 @@
+export const use = `\xffathjax{$login`; 

crates/swc/tests/fixture/issues-8xxx/8496/output/1.js

@@ -0,0 +1 @@
+export const strWithDollar="$login";export const use="$login";

crates/swc/tests/fixture/issues-8xxx/8496/output/2.js

@@ -0,0 +1 @@
+export const strWithDollar="$login";export const use="$login1";

crates/swc/tests/fixture/issues-8xxx/8496/output/3.js

@@ -0,0 +1 @@
+export const strWithDollar="$login";export const use="1$login";

crates/swc/tests/fixture/issues-8xxx/8496/output/4.js

@@ -0,0 +1 @@
+export const strWithDollar="$login";export const use="asd$login";

crates/swc/tests/fixture/issues-8xxx/8496/output/5.js

@@ -0,0 +1 @@
+export const strWithDollar="$login";export const use="$$login";

crates/swc/tests/fixture/issues-8xxx/8496/output/6.js

@@ -0,0 +1 @@
+export const strWithDollar="$login";export const use="{$login";

crates/swc/tests/fixture/issues-8xxx/8496/output/7.js

@@ -0,0 +1 @@
+export const strWithDollar="$login";export const use="{$login";

crates/swc/tests/fixture/issues-8xxx/8496/output/8.js

@@ -0,0 +1 @@
+export const use=`\xffathjax{$login`;

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

@@ -265,6 +265,43 @@ impl Pure<'_> {
         let mut cur_raw = String::new();
         let mut cur_cooked = Some(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].clone();
+
+                if q.cooked.is_some() {
+                    if let Some(cur_cooked) = &mut cur_cooked {
+                        cur_cooked.push_str("");
+                    }
+                } else {
+                    // If cooked is None, it means that the template literal contains invalid escape
+                    // sequences.
+                    cur_cooked = None;
+                }
+            } else {
+                let i = i / 2;
+                let e = &tpl.exprs[i];
+
+                match &**e {
+                    Expr::Lit(Lit::Str(s)) => {
+                        if cur_cooked.is_none() && s.raw.is_none() {
+                            return;
+                        }
+
+                        if let Some(cur_cooked) = &mut cur_cooked {
+                            cur_cooked.push_str("");
+                        }
+                    }
+                    _ => {
+                        cur_cooked = Some(String::new());
+                    }
+                }
+            }
+        }
+
+        cur_cooked = Some(Default::default());
+
         for i in 0..(tpl.exprs.len() + tpl.quasis.len()) {
             if i % 2 == 0 {
                 let i = i / 2;
@@ -286,10 +323,19 @@ impl Pure<'_> {
 
                 match *e {
                     Expr::Lit(Lit::Str(s)) => {
-                        cur_raw.push_str(&convert_str_value_to_tpl_raw(&s.value));
                         if let Some(cur_cooked) = &mut cur_cooked {
                             cur_cooked.push_str(&convert_str_value_to_tpl_cooked(&s.value));
                         }
+
+                        if let Some(raw) = &s.raw {
+                            if raw.len() >= 2 {
+                                // Exclude quotes
+                                cur_raw
+                                    .push_str(&convert_str_raw_to_tpl_raw(&raw[1..raw.len() - 1]));
+                            }
+                        } else {
+                            cur_raw.push_str(&convert_str_value_to_tpl_raw(&s.value));
+                        }
                     }
                     _ => {
                         quasis.push(TplElement {
@@ -325,6 +371,12 @@ impl Pure<'_> {
     pub(super) fn concat_tpl(&mut self, l: &mut Expr, r: &mut Expr) {
         match (&mut *l, &mut *r) {
             (Expr::Tpl(l), Expr::Lit(Lit::Str(rs))) => {
+                if let Some(raw) = &rs.raw {
+                    if raw.len() <= 2 {
+                        return;
+                    }
+                }
+
                 // Append
                 if let Some(l_last) = l.quasis.last_mut() {
                     self.changed = true;
@@ -340,15 +392,27 @@ impl Pure<'_> {
                                 .into();
                     }
 
-                    let new: Atom =
+                    l_last.raw = format!(
-                        format!("{}{}", l_last.raw, convert_str_value_to_tpl_raw(&rs.value)).into();
+                        "{}{}",
-                    l_last.raw = new;
+                        l_last.raw,
+                        rs.raw
+                            .clone()
+                            .map(|s| convert_str_raw_to_tpl_raw(&s[1..s.len() - 1]))
+                            .unwrap_or_else(|| convert_str_value_to_tpl_raw(&rs.value).into())
+                    )
+                    .into();
 
                     r.take();
                 }
             }
 
             (Expr::Lit(Lit::Str(ls)), Expr::Tpl(r)) => {
+                if let Some(raw) = &ls.raw {
+                    if raw.len() <= 2 {
+                        return;
+                    }
+                }
+
                 // Append
                 if let Some(r_first) = r.quasis.first_mut() {
                     self.changed = true;
@@ -364,8 +428,14 @@ impl Pure<'_> {
                                 .into()
                     }
 
-                    let new: Atom =
+                    let new: Atom = format!(
-                        format!("{}{}", convert_str_value_to_tpl_raw(&ls.value), r_first.raw)
+                        "{}{}",
+                        ls.raw
+                            .clone()
+                            .map(|s| convert_str_raw_to_tpl_raw(&s[1..s.len() - 1]))
+                            .unwrap_or_else(|| convert_str_value_to_tpl_raw(&ls.value).into()),
+                        r_first.raw
+                    )
                     .into();
                     r_first.raw = new;
 
@@ -392,7 +462,7 @@ impl Pure<'_> {
 
                 debug_assert!(l.quasis.len() == l.exprs.len() + 1, "{:?} is invalid", l);
                 self.changed = true;
-                report_change!("strings: Merged to template literals");
+                report_change!("strings: Merged two template literals");
             }
             _ => {}
         }
@@ -498,9 +568,9 @@ impl Pure<'_> {
 
 pub(super) fn convert_str_value_to_tpl_cooked(value: &JsWord) -> Cow<str> {
     value
-        .replace('\\', "\\\\")
+        .replace("\\\\", "\\")
-        .replace('`', "\\`")
+        .replace("\\`", "`")
-        .replace('$', "\\$")
+        .replace("\\$", "$")
         .into()
 }
 
@@ -513,3 +583,7 @@ pub(super) fn convert_str_value_to_tpl_raw(value: &JsWord) -> Cow<str> {
         .replace('\r', "\\r")
         .into()
 }
+
+pub(super) fn convert_str_raw_to_tpl_raw(value: &str) -> Atom {
+    value.replace('`', "\\`").replace('$', "\\$").into()
+}

crates/swc_ecma_minifier/tests/compress.rs

@@ -479,7 +479,7 @@ fn fixture(input: PathBuf) {
 
         let expected = {
             let expected = read_to_string(dir.join("output.js")).unwrap();
-            let fm = cm.new_source_file(FileName::Anon, expected);
+            let fm = cm.new_source_file(FileName::Custom("expected.js".into()), expected);
             let lexer = Lexer::new(
                 Default::default(),
                 Default::default(),