next-swc: add next-font-loaders to crates/core

packages/next-swc/crates/core/src/lib.rs

@@ -36,6 +36,7 @@ use serde::Deserialize;
 use std::cell::RefCell;
 use std::rc::Rc;
 use std::{path::PathBuf, sync::Arc};
+use swc_core::ecma::atoms::JsWord;
 
 use swc_core::{
     base::config::ModuleConfig,
@@ -51,6 +52,7 @@ mod auto_cjs;
 pub mod disallow_re_export_all_in_page;
 pub mod hook_optimizer;
 pub mod next_dynamic;
+pub mod next_font_loaders;
 pub mod next_ssg;
 pub mod page_config;
 pub mod react_remove_properties;
@@ -105,6 +107,9 @@ pub struct TransformOptions {
 
     #[serde(default)]
     pub modularize_imports: Option<modularize_imports::Config>,
+
+    #[serde(default)]
+    pub font_loaders: Option<Vec<JsWord>>,
 }
 
 pub fn custom_before_pass<'a, C: Comments + 'a>(
@@ -195,6 +200,11 @@ pub fn custom_before_pass<'a, C: Comments + 'a>(
         match &opts.modularize_imports {
             Some(config) => Either::Left(modularize_imports::modularize_imports(config.clone())),
             None => Either::Right(noop()),
+        },
+        match &opts.font_loaders {
+            Some(font_loaders) =>
+                Either::Left(next_font_loaders::next_font_loaders(font_loaders.clone())),
+            None => Either::Right(noop()),
         }
     )
 }

packages/next-swc/crates/core/src/next_font_loaders/find_functions_outside_module_scope.rs

@@ -0,0 +1,31 @@
+use swc_core::common::errors::HANDLER;
+use swc_core::ecma::ast::*;
+use swc_core::ecma::visit::noop_visit_type;
+use swc_core::ecma::visit::Visit;
+
+pub struct FindFunctionsOutsideModuleScope<'a> {
+    pub state: &'a super::State,
+}
+
+impl<'a> Visit for FindFunctionsOutsideModuleScope<'a> {
+    noop_visit_type!();
+
+    fn visit_ident(&mut self, ident: &Ident) {
+        if self.state.font_functions.get(&ident.to_id()).is_some()
+            && self
+                .state
+                .font_functions_in_allowed_scope
+                .get(&ident.span.lo)
+                .is_none()
+        {
+            HANDLER.with(|handler| {
+                handler
+                    .struct_span_err(
+                        ident.span,
+                        "Font loaders must be called and assigned to a const in the module scope",
+                    )
+                    .emit()
+            });
+        }
+    }
+}

packages/next-swc/crates/core/src/next_font_loaders/font_functions_collector.rs

@@ -0,0 +1,68 @@
+use swc_core::common::errors::HANDLER;
+use swc_core::ecma::ast::*;
+use swc_core::ecma::atoms::JsWord;
+use swc_core::ecma::visit::noop_visit_type;
+use swc_core::ecma::visit::Visit;
+
+pub struct FontFunctionsCollector<'a> {
+    pub font_loaders: &'a [JsWord],
+    pub state: &'a mut super::State,
+}
+
+impl<'a> Visit for FontFunctionsCollector<'a> {
+    noop_visit_type!();
+
+    fn visit_import_decl(&mut self, import_decl: &ImportDecl) {
+        if self.font_loaders.contains(&import_decl.src.value) {
+            self.state
+                .removeable_module_items
+                .insert(import_decl.span.lo);
+            for specifier in &import_decl.specifiers {
+                match specifier {
+                    ImportSpecifier::Named(ImportNamedSpecifier {
+                        local, imported, ..
+                    }) => {
+                        self.state
+                            .font_functions_in_allowed_scope
+                            .insert(local.span.lo);
+
+                        let function_name = if let Some(ModuleExportName::Ident(ident)) = imported {
+                            ident.sym.clone()
+                        } else {
+                            local.sym.clone()
+                        };
+                        self.state.font_functions.insert(
+                            local.to_id(),
+                            super::FontFunction {
+                                loader: import_decl.src.value.clone(),
+                                function_name: Some(function_name),
+                            },
+                        );
+                    }
+                    ImportSpecifier::Default(ImportDefaultSpecifier { local, .. }) => {
+                        self.state
+                            .font_functions_in_allowed_scope
+                            .insert(local.span.lo);
+                        self.state.font_functions.insert(
+                            local.to_id(),
+                            super::FontFunction {
+                                loader: import_decl.src.value.clone(),
+                                function_name: None,
+                            },
+                        );
+                    }
+                    ImportSpecifier::Namespace(_) => {
+                        HANDLER.with(|handler| {
+                            handler
+                                .struct_span_err(
+                                    import_decl.span,
+                                    "Font loaders can't have namespace imports",
+                                )
+                                .emit()
+                        });
+                    }
+                }
+            }
+        }
+    }
+}

packages/next-swc/crates/core/src/next_font_loaders/font_imports_generator.rs

@@ -0,0 +1,220 @@
+use serde_json::Value;
+use swc_core::common::errors::HANDLER;
+use swc_core::common::{Spanned, DUMMY_SP};
+use swc_core::ecma::ast::*;
+use swc_core::ecma::atoms::JsWord;
+use swc_core::ecma::visit::{noop_visit_type, Visit};
+
+pub struct FontImportsGenerator<'a> {
+    pub state: &'a mut super::State,
+}
+
+impl<'a> FontImportsGenerator<'a> {
+    fn check_call_expr(&mut self, call_expr: &CallExpr) -> Option<ImportDecl> {
+        if let Callee::Expr(callee_expr) = &call_expr.callee {
+            if let Expr::Ident(ident) = &**callee_expr {
+                if let Some(font_function) = self.state.font_functions.get(&ident.to_id()) {
+                    self.state
+                        .font_functions_in_allowed_scope
+                        .insert(ident.span.lo);
+
+                    let json: Result<Vec<Value>, ()> = call_expr
+                        .args
+                        .iter()
+                        .map(|expr_or_spread| {
+                            if let Some(span) = expr_or_spread.spread {
+                                HANDLER.with(|handler| {
+                                    handler
+                                        .struct_span_err(span, "Font loaders don't accept spreads")
+                                        .emit()
+                                });
+                            }
+
+                            expr_to_json(&*expr_or_spread.expr)
+                        })
+                        .collect();
+
+                    if let Ok(json) = json {
+                        let mut json_values: Vec<String> =
+                            json.iter().map(|value| value.to_string()).collect();
+                        let function_name = match &font_function.function_name {
+                            Some(function) => String::from(&**function),
+                            None => String::new(),
+                        };
+                        let mut values = vec![function_name];
+                        values.append(&mut json_values);
+
+                        return Some(ImportDecl {
+                            src: Str {
+                                value: JsWord::from(format!(
+                                    "{}?{}",
+                                    font_function.loader,
+                                    values.join(";")
+                                )),
+                                raw: None,
+                                span: DUMMY_SP,
+                            },
+                            specifiers: vec![],
+                            type_only: false,
+                            asserts: None,
+                            span: DUMMY_SP,
+                        });
+                    }
+                }
+            }
+        }
+
+        None
+    }
+
+    fn check_var_decl(&mut self, var_decl: &VarDecl) {
+        if let Some(decl) = var_decl.decls.get(0) {
+            let ident = match &decl.name {
+                Pat::Ident(ident) => Ok(ident.id.clone()),
+                pattern => Err(pattern),
+            };
+            if let Some(expr) = &decl.init {
+                if let Expr::Call(call_expr) = &**expr {
+                    let import_decl = self.check_call_expr(call_expr);
+
+                    if let Some(mut import_decl) = import_decl {
+                        self.state.removeable_module_items.insert(var_decl.span.lo);
+
+                        match var_decl.kind {
+                            VarDeclKind::Const => {}
+                            _ => {
+                                HANDLER.with(|handler| {
+                                    handler
+                                        .struct_span_err(
+                                            var_decl.span,
+                                            "Font loader calls must be assigned to a const",
+                                        )
+                                        .emit()
+                                });
+                            }
+                        }
+
+                        match ident {
+                            Ok(ident) => {
+                                import_decl.specifiers =
+                                    vec![ImportSpecifier::Default(ImportDefaultSpecifier {
+                                        span: DUMMY_SP,
+                                        local: ident,
+                                    })];
+
+                                self.state
+                                    .font_imports
+                                    .push(ModuleItem::ModuleDecl(ModuleDecl::Import(import_decl)));
+                            }
+                            Err(pattern) => {
+                                HANDLER.with(|handler| {
+                                    handler
+                                        .struct_span_err(
+                                            pattern.span(),
+                                            "Font loader calls must be assigned to an identifier",
+                                        )
+                                        .emit()
+                                });
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
+
+impl<'a> Visit for FontImportsGenerator<'a> {
+    noop_visit_type!();
+
+    fn visit_module_item(&mut self, item: &ModuleItem) {
+        if let ModuleItem::Stmt(Stmt::Decl(Decl::Var(var_decl))) = item {
+            self.check_var_decl(var_decl);
+        }
+    }
+}
+
+fn object_lit_to_json(object_lit: &ObjectLit) -> Value {
+    let mut values = serde_json::Map::new();
+    for prop in &object_lit.props {
+        match prop {
+            PropOrSpread::Prop(prop) => match &**prop {
+                Prop::KeyValue(key_val) => {
+                    let key = match &key_val.key {
+                        PropName::Ident(ident) => Ok(String::from(&*ident.sym)),
+                        key => {
+                            HANDLER.with(|handler| {
+                                handler
+                                    .struct_span_err(key.span(), "Unexpected object key type")
+                                    .emit()
+                            });
+                            Err(())
+                        }
+                    };
+                    let val = expr_to_json(&*key_val.value);
+                    if let (Ok(key), Ok(val)) = (key, val) {
+                        values.insert(key, val);
+                    }
+                }
+                key => HANDLER.with(|handler| {
+                    handler.struct_span_err(key.span(), "Unexpected key").emit();
+                }),
+            },
+            PropOrSpread::Spread(spread_span) => HANDLER.with(|handler| {
+                handler
+                    .struct_span_err(spread_span.dot3_token, "Unexpected spread")
+                    .emit();
+            }),
+        }
+    }
+
+    Value::Object(values)
+}
+
+fn expr_to_json(expr: &Expr) -> Result<Value, ()> {
+    match expr {
+        Expr::Lit(Lit::Str(str)) => Ok(Value::String(String::from(&*str.value))),
+        Expr::Lit(Lit::Bool(Bool { value, .. })) => Ok(Value::Bool(*value)),
+        Expr::Lit(Lit::Num(Number { value, .. })) => {
+            Ok(Value::Number(serde_json::Number::from_f64(*value).unwrap()))
+        }
+        Expr::Object(object_lit) => Ok(object_lit_to_json(object_lit)),
+        Expr::Array(ArrayLit {
+            elems,
+            span: array_span,
+            ..
+        }) => {
+            let elements: Result<Vec<Value>, ()> = elems
+                .iter()
+                .map(|e| {
+                    if let Some(expr) = e {
+                        match expr.spread {
+                            Some(spread_span) => HANDLER.with(|handler| {
+                                handler
+                                    .struct_span_err(spread_span, "Unexpected spread")
+                                    .emit();
+                                Err(())
+                            }),
+                            None => expr_to_json(&*expr.expr),
+                        }
+                    } else {
+                        HANDLER.with(|handler| {
+                            handler
+                                .struct_span_err(*array_span, "Unexpected empty value in array")
+                                .emit();
+                            Err(())
+                        })
+                    }
+                })
+                .collect();
+
+            elements.map(Value::Array)
+        }
+        lit => HANDLER.with(|handler| {
+            handler
+                .struct_span_err(lit.span(), "Unexpected value")
+                .emit();
+            Err(())
+        }),
+    }
+}