fix(es/minifier): Fix a bug about Tpl => Str (#8934)

**Description:**

I added the method to `swc_ecma_ast` to reuse it from plugins.

**Related issue:**

 - Closes #8931

crates/swc/tests/fixture/issues-8xxx/8931/input/.swcrc

@@ -0,0 +1,14 @@
+{
+    // Enable minification
+    "minify": true,
+    // Optional, configure minification options
+    "jsc": {
+        "minify": {
+            "compress": {
+                "unused": true
+            },
+            "mangle": true
+        },
+        "target": "es2018"
+    }
+}

crates/swc/tests/fixture/issues-8xxx/8931/input/1.js

@@ -0,0 +1,6 @@
+export function _jsx(a, b) {
+    return b;
+}
+
+export const a = _jsx("math", `P \\vdash q`)
+export const b = _jsx("math", "P \\vdash q")

crates/swc/tests/fixture/issues-8xxx/8931/input/2.js

@@ -0,0 +1,6 @@
+export function _jsx(a, b) {
+    return b;
+}
+
+export const a = _jsx("math", `\` \\vdash q`)
+export const b = _jsx("math", "P \\vdash q")

crates/swc/tests/fixture/issues-8xxx/8931/output/1.js

@@ -0,0 +1 @@
+export function _jsx(t,s){return s}export const a=_jsx("math","P \\vdash q");export const b=_jsx("math","P \\vdash q");

crates/swc/tests/fixture/issues-8xxx/8931/output/2.js

@@ -0,0 +1 @@
+export function _jsx(t,s){return s}export const a=_jsx("math","` \\vdash q");export const b=_jsx("math","P \\vdash q");

crates/swc_ecma_ast/src/lit.rs

@@ -196,6 +196,54 @@ impl Str {
     pub fn is_empty(&self) -> bool {
         self.value.is_empty()
     }
+
+    pub fn from_tpl_raw(tpl_raw: &str) -> Atom {
+        let mut buf = String::with_capacity(tpl_raw.len());
+
+        let mut iter = tpl_raw.chars();
+
+        while let Some(c) = iter.next() {
+            match c {
+                '\\' => {
+                    if let Some(next) = iter.next() {
+                        match next {
+                            '`' | '$' | '\\' => {
+                                buf.push(next);
+                            }
+                            'b' => {
+                                buf.push('\u{0008}');
+                            }
+                            'f' => {
+                                buf.push('\u{000C}');
+                            }
+                            'n' => {
+                                buf.push('\n');
+                            }
+                            'r' => {
+                                buf.push('\r');
+                            }
+                            't' => {
+                                buf.push('\t');
+                            }
+                            'v' => {
+                                buf.push('\u{000B}');
+                            }
+                            _ => {
+                                buf.push('\\');
+                                buf.push(next);
+                            }
+                        }
+                    }
+                }
+
+                c => {
+                    buf.push(c);
+                }
+            }
+        }
+
+        buf.into()
+    }
 }
 
 impl EqIgnoreSpan for Str {

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

@@ -220,23 +220,14 @@ impl Pure<'_> {
                     && !c.contains("\\x")
                     && !c.contains("\\u")
                 {
-                    let value = c
-                        .replace("\\`", "`")
-                        .replace("\\$", "$")
-                        .replace("\\b", "\u{0008}")
-                        .replace("\\f", "\u{000C}")
-                        .replace("\\n", "\n")
-                        .replace("\\r", "\r")
-                        .replace("\\t", "\t")
-                        .replace("\\v", "\u{000B}")
-                        .replace("\\\\", "\\");
+                    let value = Str::from_tpl_raw(c);
 
                     report_change!("converting a template literal to a string literal");
 
                     *e = Expr::Lit(Lit::Str(Str {
                         span: t.span,
                         raw: None,
-                        value: value.into(),
+                        value,
                     }));
                 }
             }