Move most of the code into new askama_shared crate

This makes it possible to share code between askama and askama_derive.

1 files changed, 0 insertions, 715 deletions

diff --git a/askama_derive/src/generator.rs b/askama_derive/src/generator.rs
deleted file mode 100644
index 82f3994..0000000
--- a/askama_derive/src/generator.rs
+++ /dev/null
@@ -1,715 +0,0 @@
-use parser::{self, Cond, Expr, Node, Target, WS};
-use path;
-
-use quote::{Tokens, ToTokens};
-
-use std::{cmp, hash, str};
-use std::path::Path;
-use std::collections::{HashMap, HashSet};
-
-use syn;
-
-pub fn generate(ast: &syn::DeriveInput, path: &Path, mut nodes: Vec<Node>) -> String {
-    let mut base: Option<Expr> = None;
-    let mut blocks = Vec::new();
-    let mut content = Vec::new();
-    let mut macros = HashMap::new();
-    for n in nodes.drain(..) {
-        match n {
-            Node::Extends(path) => {
-                match base {
-                    Some(_) => panic!("multiple extend blocks found"),
-                    None => { base = Some(path); },
-                }
-            },
-            Node::BlockDef(ws1, name, _, ws2) => {
-                blocks.push(n);
-                content.push(Node::Block(ws1, name, ws2));
-            },
-            Node::Macro(ws1, name, params, contents, ws2) => {
-                macros.insert(name, (ws1, name, params, contents, ws2));
-            },
-            _ => { content.push(n); },
-        }
-    }
-
-    let mut gen = Generator::default(&macros);
-    if !blocks.is_empty() {
-        let trait_name = trait_name_for_path(&base, path);
-        if base.is_none() {
-            gen.define_trait(&trait_name, &blocks);
-        } else {
-            let parent_type = get_parent_type(ast)
-                .expect("expected field '_parent' in extending template struct");
-            gen.deref_to_parent(ast, &parent_type);
-        }
-
-        let trait_nodes = if base.is_none() { Some(&content[..]) } else { None };
-        gen.impl_trait(ast, &trait_name, &blocks, trait_nodes);
-        gen.impl_template_for_trait(ast, base.is_some());
-    } else {
-        gen.impl_template(ast, &content);
-    }
-    gen.impl_display(ast);
-    if cfg!(feature = "iron") {
-        gen.impl_modifier_response(ast);
-    }
-    if cfg!(feature = "rocket") {
-        gen.impl_responder(ast, path);
-    }
-    gen.result()
-}
-
-fn trait_name_for_path(base: &Option<Expr>, path: &Path) -> String {
-    let rooted_path = match *base {
-        Some(Expr::StrLit(user_path)) => {
-            path::find_template_from_path(user_path, Some(path))
-        },
-        _ => path.to_path_buf(),
-    };
-
-    let mut res = String::new();
-    res.push_str("TraitFrom");
-    for c in rooted_path.to_string_lossy().chars() {
-        if c.is_alphanumeric() {
-            res.push(c);
-        } else {
-            res.push_str(&format!("{:x}", c as u32));
-        }
-    }
-    res
-}
-
-fn get_parent_type(ast: &syn::DeriveInput) -> Option<&syn::Ty> {
-    match ast.body {
-        syn::Body::Struct(ref data) => {
-            data.fields().iter().filter_map(|f| {
-                f.ident.as_ref().and_then(|name| {
-                    if name.as_ref() == "_parent" {
-                        Some(&f.ty)
-                    } else {
-                        None
-                    }
-                })
-            })
-        },
-        _ => panic!("derive(Template) only works for struct items"),
-    }.next()
-}
-
-struct Generator<'a> {
-    buf: String,
-    indent: u8,
-    start: bool,
-    locals: SetChain<'a, &'a str>,
-    next_ws: Option<&'a str>,
-    skip_ws: bool,
-    macros: &'a MacroMap<'a>,
-}
-
-impl<'a> Generator<'a> {
-
-    fn new<'n>(macros: &'n MacroMap, locals: SetChain<'n, &'n str>, indent: u8) -> Generator<'n> {
-        Generator {
-            buf: String::new(),
-            indent: indent,
-            start: true,
-            locals: locals,
-            next_ws: None,
-            skip_ws: false,
-            macros: macros,
-        }
-    }
-
-    fn default<'n>(macros: &'n MacroMap) -> Generator<'n> {
-        Self::new(macros, SetChain::new(), 0)
-    }
-
-    fn child<'n>(&'n mut self) -> Generator<'n> {
-        let locals = SetChain::with_parent(&self.locals);
-        Self::new(self.macros, locals, self.indent)
-    }
-
-    /* Helper methods for writing to internal buffer */
-
-    fn indent(&mut self) {
-        self.indent += 1;
-    }
-
-    fn dedent(&mut self) {
-        self.indent -= 1;
-    }
-
-    fn write(&mut self, s: &str) {
-        if self.start {
-            for _ in 0..(self.indent * 4) {
-                self.buf.push(' ');
-            }
-            self.start = false;
-        }
-        self.buf.push_str(s);
-    }
-
-    fn writeln(&mut self, s: &str) {
-        if s.is_empty() {
-            return;
-        }
-        if s == "}" {
-            self.dedent();
-        }
-        self.write(s);
-        if s.ends_with('{') {
-            self.indent();
-        }
-        self.buf.push('\n');
-        self.start = true;
-    }
-
-    /* Helper methods for dealing with whitespace nodes */
-
-    fn flush_ws(&mut self, ws: &WS) {
-        if self.next_ws.is_some() && !ws.0 {
-            let val = self.next_ws.unwrap();
-            if !val.is_empty() {
-                self.writeln(&format!("writer.write_str({:#?})?;",
-                                      val));
-            }
-        }
-        self.next_ws = None;
-    }
-
-    fn prepare_ws(&mut self, ws: &WS) {
-        self.skip_ws = ws.1;
-    }
-
-    fn handle_ws(&mut self, ws: &WS) {
-        self.flush_ws(ws);
-        self.prepare_ws(ws);
-    }
-
-    /* Visitor methods for expression types */
-
-    fn visit_num_lit(&mut self, s: &str) {
-        self.write(s);
-    }
-
-    fn visit_str_lit(&mut self, s: &str) {
-        self.write(&format!("\"{}\"", s));
-    }
-
-    fn visit_var(&mut self, s: &str) {
-        if self.locals.contains(s) {
-            self.write(s);
-        } else {
-            self.write(&format!("self.{}", s));
-        }
-    }
-
-    fn visit_attr(&mut self, obj: &Expr, attr: &str) {
-        if let Expr::Var(name) = *obj {
-            if name == "loop" {
-                self.write("_loop_index");
-                if attr == "index" {
-                    self.write(" + 1");
-                    return;
-                } else if attr == "index0" {
-                    return;
-                } else {
-                    panic!("unknown loop variable");
-                }
-            }
-        }
-        self.visit_expr(obj);
-        self.write(&format!(".{}", attr));
-    }
-
-    fn visit_filter(&mut self, name: &str, args: &[Expr]) {
-        if name == "format" {
-            self.write("format!(");
-        } else if BUILT_IN_FILTERS.contains(&name) {
-            self.write(&format!("::askama::filters::{}(&", name));
-        } else {
-            self.write(&format!("filters::{}(&", name));
-        }
-
-        for (i, arg) in args.iter().enumerate() {
-            if i > 0 {
-                self.write(", &");
-            }
-            self.visit_expr(arg);
-        }
-        self.write(")");
-        if name != "format" {
-            self.write("?");
-        }
-    }
-
-    fn visit_binop(&mut self, op: &str, left: &Expr, right: &Expr) {
-        self.visit_expr(left);
-        self.write(&format!(" {} ", op));
-        self.visit_expr(right);
-    }
-
-    fn visit_group(&mut self, inner: &Expr) {
-        self.write("(");
-        self.visit_expr(inner);
-        self.write(")");
-    }
-
-    fn visit_method_call(&mut self, obj: &Expr, method: &str, args: &[Expr]) {
-        self.visit_expr(obj);
-        self.write(&format!(".{}(", method));
-        for (i, arg) in args.iter().enumerate() {
-            if i > 0 {
-                self.write(", ");
-            }
-            self.visit_expr(arg);
-        }
-        self.write(")");
-    }
-
-    fn visit_expr(&mut self, expr: &Expr) {
-        match *expr {
-            Expr::NumLit(s) => self.visit_num_lit(s),
-            Expr::StrLit(s) => self.visit_str_lit(s),
-            Expr::Var(s) => self.visit_var(s),
-            Expr::Attr(ref obj, name) => self.visit_attr(obj, name),
-            Expr::Filter(name, ref args) => self.visit_filter(name, args),
-            Expr::BinOp(op, ref left, ref right) =>
-                self.visit_binop(op, left, right),
-            Expr::Group(ref inner) => self.visit_group(inner),
-            Expr::MethodCall(ref obj, method, ref args) =>
-                self.visit_method_call(obj, method, args),
-        }
-    }
-
-    fn visit_target_single<'t>(&mut self, name: &'t str) -> Vec<&'t str> {
-        vec![name]
-    }
-
-    fn visit_target<'t>(&mut self, target: &'t Target) -> Vec<&'t str> {
-        match *target {
-            Target::Name(s) => { self.visit_target_single(s) },
-        }
-    }
-
-    /* Helper methods for handling node types */
-
-    fn write_lit(&mut self, lws: &'a str, val: &str, rws: &'a str) {
-        assert!(self.next_ws.is_none());
-        if !lws.is_empty() {
-            if self.skip_ws {
-                self.skip_ws = false;
-            } else if val.is_empty() {
-                assert!(rws.is_empty());
-                self.next_ws = Some(lws);
-            } else {
-                self.writeln(&format!("writer.write_str({:#?})?;",
-                                      lws));
-            }
-        }
-        if !val.is_empty() {
-            self.writeln(&format!("writer.write_str({:#?})?;", val));
-        }
-        if !rws.is_empty() {
-            self.next_ws = Some(rws);
-        }
-    }
-
-    fn write_expr(&mut self, ws: &WS, s: &Expr) {
-        self.handle_ws(ws);
-        self.write("writer.write_fmt(format_args!(\"{}\", ");
-        self.visit_expr(s);
-        self.writeln("))?;");
-    }
-
-    fn write_call(&mut self, ws: &WS, name: &str, args: &[Expr]) {
-        self.handle_ws(ws);
-        let def = self.macros.get(name).expect(&format!("macro '{}' not found", name));
-        self.locals.push();
-        self.writeln("{");
-        self.prepare_ws(&def.0);
-        for (i, arg) in def.2.iter().enumerate() {
-            self.write(&format!("let {} = &", arg));
-            self.locals.insert(arg);
-            self.visit_expr(&args.get(i)
-                .expect(&format!("macro '{}' takes more than {} arguments", name, i)));
-            self.writeln(";");
-        }
-        self.handle(&def.3);
-        self.flush_ws(&def.4);
-        self.writeln("}");
-        self.locals.pop();
-    }
-
-    fn write_let_decl(&mut self, ws: &WS, var: &'a Target) {
-        self.handle_ws(ws);
-        self.write("let ");
-        match *var {
-            Target::Name(name) => {
-                self.locals.insert(name);
-                self.write(name);
-            },
-        }
-        self.writeln(";");
-    }
-
-    fn write_let(&mut self, ws: &WS, var: &'a Target, val: &Expr) {
-        self.handle_ws(ws);
-        match *var {
-            Target::Name(name) => {
-                if !self.locals.contains(name) {
-                    self.write("let ");
-                    self.locals.insert(name);
-                }
-                self.write(name);
-            },
-        }
-        self.write(" = ");
-        self.visit_expr(val);
-        self.writeln(";");
-    }
-
-    fn write_cond(&mut self, conds: &'a [Cond], ws: &WS) {
-        for (i, &(ref cws, ref cond, ref nodes)) in conds.iter().enumerate() {
-            self.handle_ws(cws);
-            match *cond {
-                Some(ref expr) => {
-                    if i == 0 {
-                        self.write("if ");
-                    } else {
-                        self.dedent();
-                        self.write("} else if ");
-                    }
-                    self.visit_expr(expr);
-                },
-                None => {
-                    self.dedent();
-                    self.write("} else");
-                },
-            }
-            self.writeln(" {");
-            self.locals.push();
-            self.handle(nodes);
-            self.locals.pop();
-        }
-        self.handle_ws(ws);
-        self.writeln("}");
-    }
-
-    fn write_loop(&mut self, ws1: &WS, var: &'a Target, iter: &Expr,
-                  body: &'a [Node], ws2: &WS) {
-        self.handle_ws(ws1);
-        self.locals.push();
-        self.write("for (_loop_index, ");
-        let targets = self.visit_target(var);
-        for name in &targets {
-            self.locals.insert(name);
-            self.write(name);
-        }
-        self.write(") in (&");
-        self.visit_expr(iter);
-        self.writeln(").into_iter().enumerate() {");
-
-        self.handle(body);
-        self.handle_ws(ws2);
-        self.writeln("}");
-        self.locals.pop();
-    }
-
-    fn write_block(&mut self, ws1: &WS, name: &str, ws2: &WS) {
-        self.flush_ws(ws1);
-        self.writeln(&format!("timpl.render_block_{}_into(writer)?;", name));
-        self.prepare_ws(ws2);
-    }
-
-    fn write_block_def(&mut self, ws1: &WS, name: &str, nodes: &'a [Node],
-                       ws2: &WS) {
-        self.writeln("#[allow(unused_variables)]");
-        self.writeln(&format!(
-            "fn render_block_{}_into(&self, writer: &mut ::std::fmt::Write) \
-             -> ::askama::Result<()> {{",
-            name));
-        self.prepare_ws(ws1);
-
-        self.locals.push();
-        self.handle(nodes);
-        self.locals.pop();
-
-        self.flush_ws(ws2);
-        self.writeln("Ok(())");
-        self.writeln("}");
-    }
-
-    fn handle_include(&mut self, ws: &WS, path: &str) {
-        self.prepare_ws(ws);
-        let path = path::find_template_from_path(&path, None);
-        let src = path::get_template_source(&path);
-        let nodes = parser::parse(&src);
-        let nested = {
-            let mut gen = self.child();
-            gen.handle(&nodes);
-            gen.result()
-        };
-        self.buf.push_str(&nested);
-        self.flush_ws(ws);
-    }
-
-    fn handle(&mut self, nodes: &'a [Node]) {
-        for n in nodes {
-            match *n {
-                Node::Lit(lws, val, rws) => { self.write_lit(lws, val, rws); }
-                Node::Comment() => {},
-                Node::Expr(ref ws, ref val) => { self.write_expr(ws, val); },
-                Node::LetDecl(ref ws, ref var) => { self.write_let_decl(ws, var); },
-                Node::Let(ref ws, ref var, ref val) => { self.write_let(ws, var, val); },
-                Node::Cond(ref conds, ref ws) => {
-                    self.write_cond(conds, ws);
-                },
-                Node::Loop(ref ws1, ref var, ref iter, ref body, ref ws2) => {
-                    self.write_loop(ws1, var, iter, body, ws2);
-                },
-                Node::Block(ref ws1, name, ref ws2) => {
-                    self.write_block(ws1, name, ws2);
-                },
-                Node::BlockDef(ref ws1, name, ref block_nodes, ref ws2) => {
-                    self.write_block_def(ws1, name, block_nodes, ws2);
-                }
-                Node::Include(ref ws, ref path) => {
-                    self.handle_include(ws, path);
-                },
-                Node::Call(ref ws, name, ref args) => self.write_call(ws, name, args),
-                Node::Macro(_, _, _, _, _) |
-                Node::Extends(_) => {
-                    panic!("no extends or macros allowed in content");
-                },
-            }
-        }
-    }
-
-    // Writes header for the `impl` for `TraitFromPathName` or `Template`
-    // for the given context struct.
-    fn write_header(&mut self, ast: &syn::DeriveInput, target: &str, extra_anno: &[&str]) {
-        let mut full_anno = Tokens::new();
-        let mut orig_anno = Tokens::new();
-        let need_anno = ast.generics.lifetimes.len() > 0 ||
-                        ast.generics.ty_params.len() > 0 ||
-                        extra_anno.len() > 0;
-        if need_anno {
-            full_anno.append("<");
-            orig_anno.append("<");
-        }
-
-        let (mut full_sep, mut orig_sep) = (false, false);
-        for lt in &ast.generics.lifetimes {
-            if full_sep {
-                full_anno.append(",");
-            }
-            if orig_sep {
-                orig_anno.append(",");
-            }
-            lt.to_tokens(&mut full_anno);
-            lt.to_tokens(&mut orig_anno);
-            full_sep = true;
-            orig_sep = true;
-        }
-
-        for anno in extra_anno {
-            if full_sep {
-                full_anno.append(",");
-            }
-            full_anno.append(anno);
-            full_sep = true;
-        }
-
-        for param in &ast.generics.ty_params {
-            if full_sep {
-                full_anno.append(",");
-            }
-            if orig_sep {
-                orig_anno.append(",");
-            }
-            let mut impl_param = param.clone();
-            impl_param.default = None;
-            impl_param.to_tokens(&mut full_anno);
-            param.ident.to_tokens(&mut orig_anno);
-            full_sep = true;
-            orig_sep = true;
-        }
-
-        if need_anno {
-            full_anno.append(">");
-            orig_anno.append(">");
-        }
-
-        let mut where_clause = Tokens::new();
-        ast.generics.where_clause.to_tokens(&mut where_clause);
-        self.writeln(&format!("impl{} {} for {}{}{} {{",
-                              full_anno.as_str(), target, ast.ident.as_ref(),
-                              orig_anno.as_str(), where_clause.as_str()));
-    }
-
-    // Implement `Template` for the given context struct.
-    fn impl_template(&mut self, ast: &syn::DeriveInput, nodes: &'a [Node]) {
-        self.write_header(ast, "::askama::Template", &vec![]);
-        self.writeln("fn render_into(&self, writer: &mut ::std::fmt::Write) -> \
-                      ::askama::Result<()> {");
-        self.handle(nodes);
-        self.flush_ws(&WS(false, false));
-        self.writeln("Ok(())");
-        self.writeln("}");
-        self.writeln("}");
-    }
-
-    // Implement `Display` for the given context struct.
-    fn impl_display(&mut self, ast: &syn::DeriveInput) {
-        self.write_header(ast, "::std::fmt::Display", &vec![]);
-        self.writeln("fn fmt(&self, f: &mut ::std::fmt::Formatter) -> ::std::fmt::Result {");
-        self.writeln("self.render_into(f).map_err(|_| ::std::fmt::Error {})");
-        self.writeln("}");
-        self.writeln("}");
-    }
-
-    // Implement `Deref<Parent>` for an inheriting context struct.
-    fn deref_to_parent(&mut self, ast: &syn::DeriveInput, parent_type: &syn::Ty) {
-        self.write_header(ast, "::std::ops::Deref", &vec![]);
-        let mut tokens = Tokens::new();
-        parent_type.to_tokens(&mut tokens);
-        self.writeln(&format!("type Target = {};", tokens.as_str()));
-        self.writeln("fn deref(&self) -> &Self::Target {");
-        self.writeln("&self._parent");
-        self.writeln("}");
-        self.writeln("}");
-    }
-
-    // Implement `TraitFromPathName` for the given context struct.
-    fn impl_trait(&mut self, ast: &syn::DeriveInput, trait_name: &str,
-                  blocks: &'a [Node], nodes: Option<&'a [Node]>) {
-        self.write_header(ast, &trait_name, &vec![]);
-        self.handle(blocks);
-
-        self.writeln("#[allow(unused_variables)]");
-        self.writeln(&format!(
-            "fn render_trait_into(&self, timpl: &{}, writer: &mut ::std::fmt::Write) \
-             -> ::askama::Result<()> {{",
-            trait_name));
-
-        if let Some(nodes) = nodes {
-            self.handle(nodes);
-            self.flush_ws(&WS(false, false));
-        } else {
-            self.writeln("self._parent.render_trait_into(self, writer)?;");
-        }
-
-        self.writeln("Ok(())");
-        self.writeln("}");
-        self.flush_ws(&WS(false, false));
-        self.writeln("}");
-    }
-
-    // Implement `Template` for templates that implement a template trait.
-    fn impl_template_for_trait(&mut self, ast: &syn::DeriveInput, derived: bool) {
-        self.write_header(ast, "::askama::Template", &vec![]);
-        self.writeln("fn render_into(&self, writer: &mut ::std::fmt::Write) \
-                      -> ::askama::Result<()> {");
-        if derived {
-            self.writeln("self._parent.render_trait_into(self, writer)?;");
-        } else {
-            self.writeln("self.render_trait_into(self, writer)?;");
-        }
-        self.writeln("Ok(())");
-        self.writeln("}");
-        self.writeln("}");
-    }
-
-    // Defines the `TraitFromPathName` trait.
-    fn define_trait(&mut self, trait_name: &str, blocks: &'a [Node]) {
-        self.writeln(&format!("trait {} {{", &trait_name));
-        self.handle(blocks);
-        self.writeln(&format!(
-            "fn render_trait_into(&self, timpl: &{}, writer: &mut ::std::fmt::Write) \
-             -> ::askama::Result<()>;",
-            trait_name));
-        self.writeln("}");
-    }
-
-    // Implement iron's Modifier<Response> if enabled
-    fn impl_modifier_response(&mut self, ast: &syn::DeriveInput) {
-        self.write_header(ast, "::askama::iron::Modifier<::askama::iron::Response>", &vec![]);
-        self.writeln("fn modify(self, res: &mut ::askama::iron::Response) {");
-        self.writeln("res.body = Some(Box::new(self.render().unwrap().into_bytes()));");
-        self.writeln("}");
-        self.writeln("}");
-    }
-
-    // Implement Rocket's `Responder`.
-    fn impl_responder(&mut self, ast: &syn::DeriveInput, path: &Path) {
-        self.write_header(ast, "::askama::rocket::Responder<'r>", &vec!["'r"]);
-        self.writeln("fn respond_to(self, _: &::askama::rocket::Request) \
-                      -> ::std::result::Result<\
-                         ::askama::rocket::Response<'r>, ::askama::rocket::Status> {");
-        let ext = match path.extension() {
-            Some(s) => s.to_str().unwrap(),
-            None => "txt",
-        };
-        self.writeln("::askama::rocket::Response::build()");
-        self.indent();
-        self.writeln(&format!(".header(::askama::rocket::ContentType::from_extension({:?})\
-                               .unwrap())", ext));
-        self.writeln(".sized_body(::std::io::Cursor::new(self.render().unwrap()))");
-        self.writeln(".ok()");
-        self.dedent();
-        self.writeln("}");
-        self.writeln("}");
-    }
-
-    fn result(self) -> String {
-        self.buf
-    }
-
-}
-
-struct SetChain<'a, T: 'a> where T: cmp::Eq + hash::Hash {
-    parent: Option<&'a SetChain<'a, T>>,
-    scopes: Vec<HashSet<T>>,
-}
-
-impl<'a, T: 'a> SetChain<'a, T> where T: cmp::Eq + hash::Hash {
-    fn new() -> SetChain<'a, T> {
-        SetChain { parent: None, scopes: vec![HashSet::new()] }
-    }
-    fn with_parent<'p>(parent: &'p SetChain<T>) -> SetChain<'p, T> {
-        SetChain { parent: Some(parent), scopes: vec![HashSet::new()] }
-    }
-    fn contains(&self, val: T) -> bool {
-        self.scopes.iter().rev().any(|set| set.contains(&val)) ||
-            match self.parent {
-                Some(set) => set.contains(val),
-                None => false,
-            }
-    }
-    fn insert(&mut self, val: T) {
-        self.scopes.last_mut().unwrap().insert(val);
-    }
-    fn push(&mut self) {
-        self.scopes.push(HashSet::new());
-    }
-    fn pop(&mut self) {
-        self.scopes.pop().unwrap();
-        assert!(self.scopes.len() > 0);
-    }
-}
-
-type MacroMap<'a> = HashMap<&'a str, (WS, &'a str, Vec<&'a str>, Vec<Node<'a>>, WS)>;
-
-const BUILT_IN_FILTERS: [&str; 9] = [
-    "e",
-    "escape",
-    "format",
-    "lower",
-    "lowercase",
-    "trim",
-    "upper",
-    "uppercase",
-    "json", // Optional feature; reserve the name anyway
-];