feat(es/minifier): Inline constants even if they are exported (#7583)

**Related issue:**

 - Closes #7575.

Author: kdy1

crates/swc/tests/tsc-references/taggedTemplatesWithTypeArguments1.2.minified.js

@@ -18,6 +18,6 @@ export const b = g`
 export let c = obj.prop`${(input)=>({
         ...input
     })}`;
-c.returnedObjProp.x, c.returnedObjProp.y, c.returnedObjProp.z, c = obj.prop`${(input)=>({
+c.returnedObjProp.x, c.returnedObjProp.y, c.returnedObjProp.z, (c = obj.prop`${(input)=>({
         ...input
-    })}`, c.returnedObjProp.x, c.returnedObjProp.y, c.returnedObjProp.z;
+    })}`).returnedObjProp.x, c.returnedObjProp.y, c.returnedObjProp.z;

crates/swc_ecma_minifier/src/compress/optimize/inline.rs

@@ -281,7 +281,8 @@ impl Optimizer<'_> {
             }
 
             // Single use => inlined
-            if is_inline_enabled
+            if !self.ctx.is_exported
+                && is_inline_enabled
                 && usage.declared
                 && !should_preserve
                 && !usage.reassigned()

crates/swc_ecma_minifier/src/compress/optimize/unused.rs

@@ -707,6 +707,7 @@ impl Optimizer<'_> {
                     if let Some(var) = self.data.vars.get(&i.to_id()) {
                         // technically this is inline
                         if !var.inline_prevented
+                            && !var.exported
                             && var.usage_count == 0
                             && var.declared
                             && (!var.declared_as_fn_param || !used_arguments || self.ctx.in_strict)

crates/swc_ecma_minifier/src/program_data.rs

@@ -509,6 +509,10 @@ impl VarDataLike for VarUsageInfo {
         self.inline_prevented = true;
     }
 
+    fn mark_as_exported(&mut self) {
+        self.exported = true;
+    }
+
     fn mark_initialized_with_safe_value(&mut self) {
         self.no_side_effect_for_member_access = true;
     }

crates/swc_ecma_minifier/tests/fixture/issues/7575/1/input.js

@@ -0,0 +1,18 @@
+export const envKey = "staging" || "production"
+
+const environmentResolver = () => {
+    if (envKey === "production") {
+        return "production"
+    }
+    if (envKey === "staging") {
+        return "staging"
+    }
+    if (envKey === "test") {
+        return "test"
+    }
+    if (envKey === "development") {
+        return "development"
+    }
+    throw new Error(`Unknown environment: ${envKey}`)
+}
+export const environment = environmentResolver()

crates/swc_ecma_minifier/tests/fixture/issues/7575/1/output.js

@@ -0,0 +1,2 @@
+export const envKey = "staging";
+export const environment = "staging";

crates/swc_ecma_usage_analyzer/src/analyzer/mod.rs

@@ -523,7 +523,7 @@ where
                 let ids = find_pat_ids(v);
 
                 for id in ids {
-                    self.data.var_or_default(id).prevent_inline();
+                    self.data.var_or_default(id).mark_as_exported();
                 }
             }
             _ => {}

crates/swc_ecma_usage_analyzer/src/analyzer/storage.rs

@@ -72,6 +72,8 @@ pub trait VarDataLike: Sized {
 
     fn prevent_inline(&mut self);
 
+    fn mark_as_exported(&mut self);
+
     fn mark_initialized_with_safe_value(&mut self);
 
     fn mark_as_pure_fn(&mut self);