--- /dev/null
+// Copyright 2018 Guillaume Pinot (@TeXitoi) <texitoi@texitoi.eu>
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use crate::doc_comments::process_doc_comment;
+use crate::{parse::*, spanned::Sp, ty::Ty};
+
+use std::env;
+
+use heck::{CamelCase, KebabCase, MixedCase, ShoutySnakeCase, SnakeCase};
+use proc_macro2::{Span, TokenStream};
+use proc_macro_error::abort;
+use quote::{quote, quote_spanned, ToTokens};
+use syn::{
+ self, ext::IdentExt, spanned::Spanned, Attribute, Expr, Ident, LitStr, MetaNameValue, Type,
+};
+
+#[derive(Clone)]
+pub enum Kind {
+ Arg(Sp<Ty>),
+ Subcommand(Sp<Ty>),
+ ExternalSubcommand,
+ Flatten,
+ Skip(Option<Expr>),
+}
+
+#[derive(Clone)]
+pub struct Method {
+ name: Ident,
+ args: TokenStream,
+}
+
+#[derive(Clone)]
+pub struct Parser {
+ pub kind: Sp<ParserKind>,
+ pub func: TokenStream,
+}
+
+#[derive(Debug, PartialEq, Clone)]
+pub enum ParserKind {
+ FromStr,
+ TryFromStr,
+ FromOsStr,
+ TryFromOsStr,
+ FromOccurrences,
+ FromFlag,
+}
+
+/// Defines the casing for the attributes long representation.
+#[derive(Copy, Clone, Debug, PartialEq)]
+pub enum CasingStyle {
+ /// Indicate word boundaries with uppercase letter, excluding the first word.
+ Camel,
+ /// Keep all letters lowercase and indicate word boundaries with hyphens.
+ Kebab,
+ /// Indicate word boundaries with uppercase letter, including the first word.
+ Pascal,
+ /// Keep all letters uppercase and indicate word boundaries with underscores.
+ ScreamingSnake,
+ /// Keep all letters lowercase and indicate word boundaries with underscores.
+ Snake,
+ /// Use the original attribute name defined in the code.
+ Verbatim,
+ /// Keep all letters lowercase and remove word boundaries.
+ Lower,
+ /// Keep all letters uppercase and remove word boundaries.
+ Upper,
+}
+
+#[derive(Clone)]
+pub enum Name {
+ Derived(Ident),
+ Assigned(TokenStream),
+}
+
+#[derive(Clone)]
+pub struct Attrs {
+ name: Name,
+ casing: Sp<CasingStyle>,
+ env_casing: Sp<CasingStyle>,
+ ty: Option<Type>,
+ doc_comment: Vec<Method>,
+ methods: Vec<Method>,
+ parser: Sp<Parser>,
+ author: Option<Method>,
+ about: Option<Method>,
+ version: Option<Method>,
+ no_version: Option<Ident>,
+ verbatim_doc_comment: Option<Ident>,
+ has_custom_parser: bool,
+ kind: Sp<Kind>,
+}
+
+impl Method {
+ pub fn new(name: Ident, args: TokenStream) -> Self {
+ Method { name, args }
+ }
+
+ fn from_lit_or_env(ident: Ident, lit: Option<LitStr>, env_var: &str) -> Option<Self> {
+ let mut lit = match lit {
+ Some(lit) => lit,
+
+ None => match env::var(env_var) {
+ Ok(val) => LitStr::new(&val, ident.span()),
+ Err(_) => {
+ abort!(ident,
+ "cannot derive `{}` from Cargo.toml", ident;
+ note = "`{}` environment variable is not set", env_var;
+ help = "use `{} = \"...\"` to set {} manually", ident, ident;
+ );
+ }
+ },
+ };
+
+ if ident == "author" {
+ let edited = process_author_str(&lit.value());
+ lit = LitStr::new(&edited, lit.span());
+ }
+
+ Some(Method::new(ident, quote!(#lit)))
+ }
+}
+
+impl ToTokens for Method {
+ fn to_tokens(&self, ts: &mut TokenStream) {
+ let Method { ref name, ref args } = self;
+ quote!(.#name(#args)).to_tokens(ts);
+ }
+}
+
+impl Parser {
+ fn default_spanned(span: Span) -> Sp<Self> {
+ let kind = Sp::new(ParserKind::TryFromStr, span);
+ let func = quote_spanned!(span=> ::std::str::FromStr::from_str);
+ Sp::new(Parser { kind, func }, span)
+ }
+
+ fn from_spec(parse_ident: Ident, spec: ParserSpec) -> Sp<Self> {
+ use ParserKind::*;
+
+ let kind = match &*spec.kind.to_string() {
+ "from_str" => FromStr,
+ "try_from_str" => TryFromStr,
+ "from_os_str" => FromOsStr,
+ "try_from_os_str" => TryFromOsStr,
+ "from_occurrences" => FromOccurrences,
+ "from_flag" => FromFlag,
+ s => abort!(spec.kind, "unsupported parser `{}`", s),
+ };
+
+ let func = match spec.parse_func {
+ None => match kind {
+ FromStr | FromOsStr => {
+ quote_spanned!(spec.kind.span()=> ::std::convert::From::from)
+ }
+ TryFromStr => quote_spanned!(spec.kind.span()=> ::std::str::FromStr::from_str),
+ TryFromOsStr => abort!(
+ spec.kind,
+ "you must set parser for `try_from_os_str` explicitly"
+ ),
+ FromOccurrences => quote_spanned!(spec.kind.span()=> { |v| v as _ }),
+ FromFlag => quote_spanned!(spec.kind.span()=> ::std::convert::From::from),
+ },
+
+ Some(func) => match func {
+ syn::Expr::Path(_) => quote!(#func),
+ _ => abort!(func, "`parse` argument must be a function path"),
+ },
+ };
+
+ let kind = Sp::new(kind, spec.kind.span());
+ let parser = Parser { kind, func };
+ Sp::new(parser, parse_ident.span())
+ }
+}
+
+impl CasingStyle {
+ fn from_lit(name: LitStr) -> Sp<Self> {
+ use CasingStyle::*;
+
+ let normalized = name.value().to_camel_case().to_lowercase();
+ let cs = |kind| Sp::new(kind, name.span());
+
+ match normalized.as_ref() {
+ "camel" | "camelcase" => cs(Camel),
+ "kebab" | "kebabcase" => cs(Kebab),
+ "pascal" | "pascalcase" => cs(Pascal),
+ "screamingsnake" | "screamingsnakecase" => cs(ScreamingSnake),
+ "snake" | "snakecase" => cs(Snake),
+ "verbatim" | "verbatimcase" => cs(Verbatim),
+ "lower" | "lowercase" => cs(Lower),
+ "upper" | "uppercase" => cs(Upper),
+ s => abort!(name, "unsupported casing: `{}`", s),
+ }
+ }
+}
+
+impl Name {
+ pub fn translate(self, style: CasingStyle) -> TokenStream {
+ use CasingStyle::*;
+
+ match self {
+ Name::Assigned(tokens) => tokens,
+ Name::Derived(ident) => {
+ let s = ident.unraw().to_string();
+ let s = match style {
+ Pascal => s.to_camel_case(),
+ Kebab => s.to_kebab_case(),
+ Camel => s.to_mixed_case(),
+ ScreamingSnake => s.to_shouty_snake_case(),
+ Snake => s.to_snake_case(),
+ Verbatim => s,
+ Lower => s.to_snake_case().replace("_", ""),
+ Upper => s.to_shouty_snake_case().replace("_", ""),
+ };
+ quote_spanned!(ident.span()=> #s)
+ }
+ }
+ }
+}
+
+impl Attrs {
+ fn new(
+ default_span: Span,
+ name: Name,
+ parent_attrs: Option<&Attrs>,
+ ty: Option<Type>,
+ casing: Sp<CasingStyle>,
+ env_casing: Sp<CasingStyle>,
+ ) -> Self {
+ let no_version = parent_attrs
+ .as_ref()
+ .map(|attrs| attrs.no_version.clone())
+ .unwrap_or(None);
+
+ Self {
+ name,
+ ty,
+ casing,
+ env_casing,
+ doc_comment: vec![],
+ methods: vec![],
+ parser: Parser::default_spanned(default_span),
+ about: None,
+ author: None,
+ version: None,
+ no_version,
+ verbatim_doc_comment: None,
+
+ has_custom_parser: false,
+ kind: Sp::new(Kind::Arg(Sp::new(Ty::Other, default_span)), default_span),
+ }
+ }
+
+ fn push_method(&mut self, name: Ident, arg: impl ToTokens) {
+ if name == "name" {
+ self.name = Name::Assigned(quote!(#arg));
+ } else if name == "version" {
+ self.version = Some(Method::new(name, quote!(#arg)));
+ } else {
+ self.methods.push(Method::new(name, quote!(#arg)))
+ }
+ }
+
+ fn push_attrs(&mut self, attrs: &[Attribute]) {
+ use crate::parse::StructOptAttr::*;
+
+ for attr in parse_structopt_attributes(attrs) {
+ match attr {
+ Short(ident) | Long(ident) => {
+ self.push_method(ident, self.name.clone().translate(*self.casing));
+ }
+
+ Env(ident) => {
+ self.push_method(ident, self.name.clone().translate(*self.env_casing));
+ }
+
+ Subcommand(ident) => {
+ let ty = Sp::call_site(Ty::Other);
+ let kind = Sp::new(Kind::Subcommand(ty), ident.span());
+ self.set_kind(kind);
+ }
+
+ ExternalSubcommand(ident) => {
+ self.kind = Sp::new(Kind::ExternalSubcommand, ident.span());
+ }
+
+ Flatten(ident) => {
+ let kind = Sp::new(Kind::Flatten, ident.span());
+ self.set_kind(kind);
+ }
+
+ Skip(ident, expr) => {
+ let kind = Sp::new(Kind::Skip(expr), ident.span());
+ self.set_kind(kind);
+ }
+
+ NoVersion(ident) => self.no_version = Some(ident),
+
+ VerbatimDocComment(ident) => self.verbatim_doc_comment = Some(ident),
+
+ DefaultValue(ident, lit) => {
+ let val = if let Some(lit) = lit {
+ quote!(#lit)
+ } else {
+ let ty = if let Some(ty) = self.ty.as_ref() {
+ ty
+ } else {
+ abort!(
+ ident,
+ "#[structopt(default_value)] (without an argument) can be used \
+ only on field level";
+
+ note = "see \
+ https://docs.rs/structopt/0.3.5/structopt/#magical-methods")
+ };
+
+ quote_spanned!(ident.span()=> {
+ ::structopt::lazy_static::lazy_static! {
+ static ref DEFAULT_VALUE: &'static str = {
+ let val = <#ty as ::std::default::Default>::default();
+ let s = ::std::string::ToString::to_string(&val);
+ ::std::boxed::Box::leak(s.into_boxed_str())
+ };
+ }
+ *DEFAULT_VALUE
+ })
+ };
+
+ self.methods.push(Method::new(ident, val));
+ }
+
+ About(ident, about) => {
+ self.about = Method::from_lit_or_env(ident, about, "CARGO_PKG_DESCRIPTION");
+ }
+
+ Author(ident, author) => {
+ self.author = Method::from_lit_or_env(ident, author, "CARGO_PKG_AUTHORS");
+ }
+
+ Version(ident, version) => {
+ self.push_method(ident, version);
+ }
+
+ NameLitStr(name, lit) => {
+ self.push_method(name, lit);
+ }
+
+ NameExpr(name, expr) => {
+ self.push_method(name, expr);
+ }
+
+ MethodCall(name, args) => self.push_method(name, quote!(#(#args),*)),
+
+ RenameAll(_, casing_lit) => {
+ self.casing = CasingStyle::from_lit(casing_lit);
+ }
+
+ RenameAllEnv(_, casing_lit) => {
+ self.env_casing = CasingStyle::from_lit(casing_lit);
+ }
+
+ Parse(ident, spec) => {
+ self.has_custom_parser = true;
+ self.parser = Parser::from_spec(ident, spec);
+ }
+ }
+ }
+ }
+
+ fn push_doc_comment(&mut self, attrs: &[Attribute], name: &str) {
+ use crate::Lit::*;
+ use crate::Meta::*;
+
+ let comment_parts: Vec<_> = attrs
+ .iter()
+ .filter(|attr| attr.path.is_ident("doc"))
+ .filter_map(|attr| {
+ if let Ok(NameValue(MetaNameValue { lit: Str(s), .. })) = attr.parse_meta() {
+ Some(s.value())
+ } else {
+ // non #[doc = "..."] attributes are not our concern
+ // we leave them for rustc to handle
+ None
+ }
+ })
+ .collect();
+
+ self.doc_comment =
+ process_doc_comment(comment_parts, name, self.verbatim_doc_comment.is_none());
+ }
+
+ pub fn from_struct(
+ span: Span,
+ attrs: &[Attribute],
+ name: Name,
+ parent_attrs: Option<&Attrs>,
+ argument_casing: Sp<CasingStyle>,
+ env_casing: Sp<CasingStyle>,
+ ) -> Self {
+ let mut res = Self::new(span, name, parent_attrs, None, argument_casing, env_casing);
+ res.push_attrs(attrs);
+ res.push_doc_comment(attrs, "about");
+
+ if res.has_custom_parser {
+ abort!(
+ res.parser.span(),
+ "`parse` attribute is only allowed on fields"
+ );
+ }
+ match &*res.kind {
+ Kind::Subcommand(_) => abort!(res.kind.span(), "subcommand is only allowed on fields"),
+ Kind::Skip(_) => abort!(res.kind.span(), "skip is only allowed on fields"),
+ Kind::Arg(_) | Kind::ExternalSubcommand | Kind::Flatten => res,
+ }
+ }
+
+ pub fn from_field(
+ field: &syn::Field,
+ parent_attrs: Option<&Attrs>,
+ struct_casing: Sp<CasingStyle>,
+ env_casing: Sp<CasingStyle>,
+ ) -> Self {
+ let name = field.ident.clone().unwrap();
+ let mut res = Self::new(
+ field.span(),
+ Name::Derived(name),
+ parent_attrs,
+ Some(field.ty.clone()),
+ struct_casing,
+ env_casing,
+ );
+ res.push_attrs(&field.attrs);
+ res.push_doc_comment(&field.attrs, "help");
+
+ match &*res.kind {
+ Kind::Flatten => {
+ if res.has_custom_parser {
+ abort!(
+ res.parser.span(),
+ "parse attribute is not allowed for flattened entry"
+ );
+ }
+ if res.has_explicit_methods() {
+ abort!(
+ res.kind.span(),
+ "methods are not allowed for flattened entry"
+ );
+ }
+
+ if res.has_doc_methods() {
+ res.doc_comment = vec![];
+ }
+ }
+
+ Kind::ExternalSubcommand => {}
+
+ Kind::Subcommand(_) => {
+ if res.has_custom_parser {
+ abort!(
+ res.parser.span(),
+ "parse attribute is not allowed for subcommand"
+ );
+ }
+ if res.has_explicit_methods() {
+ abort!(
+ res.kind.span(),
+ "methods in attributes are not allowed for subcommand"
+ );
+ }
+
+ let ty = Ty::from_syn_ty(&field.ty);
+ match *ty {
+ Ty::OptionOption => {
+ abort!(
+ field.ty,
+ "Option<Option<T>> type is not allowed for subcommand"
+ );
+ }
+ Ty::OptionVec => {
+ abort!(
+ field.ty,
+ "Option<Vec<T>> type is not allowed for subcommand"
+ );
+ }
+ _ => (),
+ }
+
+ res.kind = Sp::new(Kind::Subcommand(ty), res.kind.span());
+ }
+ Kind::Skip(_) => {
+ if res.has_explicit_methods() {
+ abort!(
+ res.kind.span(),
+ "methods are not allowed for skipped fields"
+ );
+ }
+ }
+ Kind::Arg(orig_ty) => {
+ let mut ty = Ty::from_syn_ty(&field.ty);
+ if res.has_custom_parser {
+ match *ty {
+ Ty::Option | Ty::Vec | Ty::OptionVec => (),
+ _ => ty = Sp::new(Ty::Other, ty.span()),
+ }
+ }
+
+ match *ty {
+ Ty::Bool => {
+ if res.is_positional() && !res.has_custom_parser {
+ abort!(field.ty,
+ "`bool` cannot be used as positional parameter with default parser";
+ help = "if you want to create a flag add `long` or `short`";
+ help = "If you really want a boolean parameter \
+ add an explicit parser, for example `parse(try_from_str)`";
+ note = "see also https://github.com/TeXitoi/structopt/tree/master/examples/true_or_false.rs";
+ )
+ }
+ if let Some(m) = res.find_method("default_value") {
+ abort!(m.name, "default_value is meaningless for bool")
+ }
+ if let Some(m) = res.find_method("required") {
+ abort!(m.name, "required is meaningless for bool")
+ }
+ }
+ Ty::Option => {
+ if let Some(m) = res.find_method("default_value") {
+ abort!(m.name, "default_value is meaningless for Option")
+ }
+ if let Some(m) = res.find_method("required") {
+ abort!(m.name, "required is meaningless for Option")
+ }
+ }
+ Ty::OptionOption => {
+ if res.is_positional() {
+ abort!(
+ field.ty,
+ "Option<Option<T>> type is meaningless for positional argument"
+ )
+ }
+ }
+ Ty::OptionVec => {
+ if res.is_positional() {
+ abort!(
+ field.ty,
+ "Option<Vec<T>> type is meaningless for positional argument"
+ )
+ }
+ }
+
+ _ => (),
+ }
+ res.kind = Sp::new(Kind::Arg(ty), orig_ty.span());
+ }
+ }
+
+ res
+ }
+
+ fn set_kind(&mut self, kind: Sp<Kind>) {
+ if let Kind::Arg(_) = *self.kind {
+ self.kind = kind;
+ } else {
+ abort!(
+ kind.span(),
+ "subcommand, flatten and skip cannot be used together"
+ );
+ }
+ }
+
+ pub fn has_method(&self, name: &str) -> bool {
+ self.find_method(name).is_some()
+ }
+
+ pub fn find_method(&self, name: &str) -> Option<&Method> {
+ self.methods.iter().find(|m| m.name == name)
+ }
+
+ /// generate methods from attributes on top of struct or enum
+ pub fn top_level_methods(&self) -> TokenStream {
+ let author = &self.author;
+ let about = &self.about;
+ let methods = &self.methods;
+ let doc_comment = &self.doc_comment;
+
+ quote!( #(#doc_comment)* #author #about #(#methods)* )
+ }
+
+ /// generate methods on top of a field
+ pub fn field_methods(&self) -> TokenStream {
+ let methods = &self.methods;
+ let doc_comment = &self.doc_comment;
+ quote!( #(#doc_comment)* #(#methods)* )
+ }
+
+ pub fn version(&self) -> TokenStream {
+ match (&self.no_version, &self.version) {
+ (None, Some(m)) => m.to_token_stream(),
+
+ (None, None) => std::env::var("CARGO_PKG_VERSION")
+ .map(|version| quote!( .version(#version) ))
+ .unwrap_or_default(),
+
+ _ => quote!(),
+ }
+ }
+
+ pub fn cased_name(&self) -> TokenStream {
+ self.name.clone().translate(*self.casing)
+ }
+
+ pub fn parser(&self) -> &Sp<Parser> {
+ &self.parser
+ }
+
+ pub fn kind(&self) -> Sp<Kind> {
+ self.kind.clone()
+ }
+
+ pub fn casing(&self) -> Sp<CasingStyle> {
+ self.casing.clone()
+ }
+
+ pub fn env_casing(&self) -> Sp<CasingStyle> {
+ self.env_casing.clone()
+ }
+
+ pub fn is_positional(&self) -> bool {
+ self.methods
+ .iter()
+ .all(|m| m.name != "long" && m.name != "short")
+ }
+
+ pub fn has_explicit_methods(&self) -> bool {
+ self.methods
+ .iter()
+ .any(|m| m.name != "help" && m.name != "long_help")
+ }
+
+ pub fn has_doc_methods(&self) -> bool {
+ !self.doc_comment.is_empty()
+ || self.methods.iter().any(|m| {
+ m.name == "help"
+ || m.name == "long_help"
+ || m.name == "about"
+ || m.name == "long_about"
+ })
+ }
+}
+
+/// replace all `:` with `, ` when not inside the `<>`
+///
+/// `"author1:author2:author3" => "author1, author2, author3"`
+/// `"author1 <http://website1.com>:author2" => "author1 <http://website1.com>, author2"
+fn process_author_str(author: &str) -> String {
+ let mut res = String::with_capacity(author.len());
+ let mut inside_angle_braces = 0usize;
+
+ for ch in author.chars() {
+ if inside_angle_braces > 0 && ch == '>' {
+ inside_angle_braces -= 1;
+ res.push(ch);
+ } else if ch == '<' {
+ inside_angle_braces += 1;
+ res.push(ch);
+ } else if inside_angle_braces == 0 && ch == ':' {
+ res.push_str(", ");
+ } else {
+ res.push(ch);
+ }
+ }
+
+ res
+}
projects / rustc.git / blobdiff