Adding upstream version 0.70.1+ds1.upstream/0.70.1+ds1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

8 files changed, 852 insertions, 0 deletions

diff --git a/crates/cargo-platform/Cargo.toml b/crates/cargo-platform/Cargo.toml
new file mode 100644
index 0000000..9a31170
--- /dev/null
+++ b/crates/cargo-platform/Cargo.toml
@@ -0,0 +1,12 @@
+[package]
+name = "cargo-platform"
+version = "0.1.2"
+edition = "2021"
+license = "MIT OR Apache-2.0"
+homepage = "https://github.com/rust-lang/cargo"
+repository = "https://github.com/rust-lang/cargo"
+documentation = "https://docs.rs/cargo-platform"
+description = "Cargo's representation of a target platform."
+
+[dependencies]
+serde = { version = "1.0.82", features = ['derive'] }
diff --git a/crates/cargo-platform/LICENSE-APACHE b/crates/cargo-platform/LICENSE-APACHE
new file mode 120000
index 0000000..1cd601d
--- /dev/null
+++ b/crates/cargo-platform/LICENSE-APACHE
@@ -0,0 +1 @@
+../../LICENSE-APACHE
\ No newline at end of file
diff --git a/crates/cargo-platform/LICENSE-MIT b/crates/cargo-platform/LICENSE-MIT
new file mode 120000
index 0000000..b2cfbdc
--- /dev/null
+++ b/crates/cargo-platform/LICENSE-MIT
@@ -0,0 +1 @@
+../../LICENSE-MIT
\ No newline at end of file
diff --git a/crates/cargo-platform/examples/matches.rs b/crates/cargo-platform/examples/matches.rs
new file mode 100644
index 0000000..9ad5d10
--- /dev/null
+++ b/crates/cargo-platform/examples/matches.rs
@@ -0,0 +1,55 @@
+//! This example demonstrates how to filter a Platform based on the current
+//! host target.
+
+use cargo_platform::{Cfg, Platform};
+use std::process::Command;
+use std::str::FromStr;
+
+static EXAMPLES: &[&str] = &[
+    "cfg(windows)",
+    "cfg(unix)",
+    "cfg(target_os=\"macos\")",
+    "cfg(target_os=\"linux\")",
+    "cfg(any(target_arch=\"x86\", target_arch=\"x86_64\"))",
+];
+
+fn main() {
+    let target = get_target();
+    let cfgs = get_cfgs();
+    println!("host target={} cfgs:", target);
+    for cfg in &cfgs {
+        println!("  {}", cfg);
+    }
+    let mut examples: Vec<&str> = EXAMPLES.iter().copied().collect();
+    examples.push(target.as_str());
+    for example in examples {
+        let p = Platform::from_str(example).unwrap();
+        println!("{:?} matches: {:?}", example, p.matches(&target, &cfgs));
+    }
+}
+
+fn get_target() -> String {
+    let output = Command::new("rustc")
+        .arg("-Vv")
+        .output()
+        .expect("rustc failed to run");
+    let stdout = String::from_utf8(output.stdout).unwrap();
+    for line in stdout.lines() {
+        if line.starts_with("host: ") {
+            return String::from(&line[6..]);
+        }
+    }
+    panic!("Failed to find host: {}", stdout);
+}
+
+fn get_cfgs() -> Vec<Cfg> {
+    let output = Command::new("rustc")
+        .arg("--print=cfg")
+        .output()
+        .expect("rustc failed to run");
+    let stdout = String::from_utf8(output.stdout).unwrap();
+    stdout
+        .lines()
+        .map(|line| Cfg::from_str(line).unwrap())
+        .collect()
+}
diff --git a/crates/cargo-platform/src/cfg.rs b/crates/cargo-platform/src/cfg.rs
new file mode 100644
index 0000000..c3ddb69
--- /dev/null
+++ b/crates/cargo-platform/src/cfg.rs
@@ -0,0 +1,319 @@
+use crate::error::{ParseError, ParseErrorKind::*};
+use std::fmt;
+use std::iter;
+use std::str::{self, FromStr};
+
+/// A cfg expression.
+#[derive(Eq, PartialEq, Hash, Ord, PartialOrd, Clone, Debug)]
+pub enum CfgExpr {
+    Not(Box<CfgExpr>),
+    All(Vec<CfgExpr>),
+    Any(Vec<CfgExpr>),
+    Value(Cfg),
+}
+
+/// A cfg value.
+#[derive(Eq, PartialEq, Hash, Ord, PartialOrd, Clone, Debug)]
+pub enum Cfg {
+    /// A named cfg value, like `unix`.
+    Name(String),
+    /// A key/value cfg pair, like `target_os = "linux"`.
+    KeyPair(String, String),
+}
+
+#[derive(PartialEq)]
+enum Token<'a> {
+    LeftParen,
+    RightParen,
+    Ident(&'a str),
+    Comma,
+    Equals,
+    String(&'a str),
+}
+
+#[derive(Clone)]
+struct Tokenizer<'a> {
+    s: iter::Peekable<str::CharIndices<'a>>,
+    orig: &'a str,
+}
+
+struct Parser<'a> {
+    t: Tokenizer<'a>,
+}
+
+impl FromStr for Cfg {
+    type Err = ParseError;
+
+    fn from_str(s: &str) -> Result<Cfg, Self::Err> {
+        let mut p = Parser::new(s);
+        let e = p.cfg()?;
+        if let Some(rest) = p.rest() {
+            return Err(ParseError::new(
+                p.t.orig,
+                UnterminatedExpression(rest.to_string()),
+            ));
+        }
+        Ok(e)
+    }
+}
+
+impl fmt::Display for Cfg {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match *self {
+            Cfg::Name(ref s) => s.fmt(f),
+            Cfg::KeyPair(ref k, ref v) => write!(f, "{} = \"{}\"", k, v),
+        }
+    }
+}
+
+impl CfgExpr {
+    /// Utility function to check if the key, "cfg(..)" matches the `target_cfg`
+    pub fn matches_key(key: &str, target_cfg: &[Cfg]) -> bool {
+        if key.starts_with("cfg(") && key.ends_with(')') {
+            let cfg = &key[4..key.len() - 1];
+
+            CfgExpr::from_str(cfg)
+                .ok()
+                .map(|ce| ce.matches(target_cfg))
+                .unwrap_or(false)
+        } else {
+            false
+        }
+    }
+
+    pub fn matches(&self, cfg: &[Cfg]) -> bool {
+        match *self {
+            CfgExpr::Not(ref e) => !e.matches(cfg),
+            CfgExpr::All(ref e) => e.iter().all(|e| e.matches(cfg)),
+            CfgExpr::Any(ref e) => e.iter().any(|e| e.matches(cfg)),
+            CfgExpr::Value(ref e) => cfg.contains(e),
+        }
+    }
+}
+
+impl FromStr for CfgExpr {
+    type Err = ParseError;
+
+    fn from_str(s: &str) -> Result<CfgExpr, Self::Err> {
+        let mut p = Parser::new(s);
+        let e = p.expr()?;
+        if let Some(rest) = p.rest() {
+            return Err(ParseError::new(
+                p.t.orig,
+                UnterminatedExpression(rest.to_string()),
+            ));
+        }
+        Ok(e)
+    }
+}
+
+impl fmt::Display for CfgExpr {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match *self {
+            CfgExpr::Not(ref e) => write!(f, "not({})", e),
+            CfgExpr::All(ref e) => write!(f, "all({})", CommaSep(e)),
+            CfgExpr::Any(ref e) => write!(f, "any({})", CommaSep(e)),
+            CfgExpr::Value(ref e) => write!(f, "{}", e),
+        }
+    }
+}
+
+struct CommaSep<'a, T>(&'a [T]);
+
+impl<'a, T: fmt::Display> fmt::Display for CommaSep<'a, T> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        for (i, v) in self.0.iter().enumerate() {
+            if i > 0 {
+                write!(f, ", ")?;
+            }
+            write!(f, "{}", v)?;
+        }
+        Ok(())
+    }
+}
+
+impl<'a> Parser<'a> {
+    fn new(s: &'a str) -> Parser<'a> {
+        Parser {
+            t: Tokenizer {
+                s: s.char_indices().peekable(),
+                orig: s,
+            },
+        }
+    }
+
+    fn expr(&mut self) -> Result<CfgExpr, ParseError> {
+        match self.peek() {
+            Some(Ok(Token::Ident(op @ "all"))) | Some(Ok(Token::Ident(op @ "any"))) => {
+                self.t.next();
+                let mut e = Vec::new();
+                self.eat(&Token::LeftParen)?;
+                while !self.r#try(&Token::RightParen) {
+                    e.push(self.expr()?);
+                    if !self.r#try(&Token::Comma) {
+                        self.eat(&Token::RightParen)?;
+                        break;
+                    }
+                }
+                if op == "all" {
+                    Ok(CfgExpr::All(e))
+                } else {
+                    Ok(CfgExpr::Any(e))
+                }
+            }
+            Some(Ok(Token::Ident("not"))) => {
+                self.t.next();
+                self.eat(&Token::LeftParen)?;
+                let e = self.expr()?;
+                self.eat(&Token::RightParen)?;
+                Ok(CfgExpr::Not(Box::new(e)))
+            }
+            Some(Ok(..)) => self.cfg().map(CfgExpr::Value),
+            Some(Err(..)) => Err(self.t.next().unwrap().err().unwrap()),
+            None => Err(ParseError::new(
+                self.t.orig,
+                IncompleteExpr("start of a cfg expression"),
+            )),
+        }
+    }
+
+    fn cfg(&mut self) -> Result<Cfg, ParseError> {
+        match self.t.next() {
+            Some(Ok(Token::Ident(name))) => {
+                let e = if self.r#try(&Token::Equals) {
+                    let val = match self.t.next() {
+                        Some(Ok(Token::String(s))) => s,
+                        Some(Ok(t)) => {
+                            return Err(ParseError::new(
+                                self.t.orig,
+                                UnexpectedToken {
+                                    expected: "a string",
+                                    found: t.classify(),
+                                },
+                            ))
+                        }
+                        Some(Err(e)) => return Err(e),
+                        None => {
+                            return Err(ParseError::new(self.t.orig, IncompleteExpr("a string")))
+                        }
+                    };
+                    Cfg::KeyPair(name.to_string(), val.to_string())
+                } else {
+                    Cfg::Name(name.to_string())
+                };
+                Ok(e)
+            }
+            Some(Ok(t)) => Err(ParseError::new(
+                self.t.orig,
+                UnexpectedToken {
+                    expected: "identifier",
+                    found: t.classify(),
+                },
+            )),
+            Some(Err(e)) => Err(e),
+            None => Err(ParseError::new(self.t.orig, IncompleteExpr("identifier"))),
+        }
+    }
+
+    fn peek(&mut self) -> Option<Result<Token<'a>, ParseError>> {
+        self.t.clone().next()
+    }
+
+    fn r#try(&mut self, token: &Token<'a>) -> bool {
+        match self.peek() {
+            Some(Ok(ref t)) if token == t => {}
+            _ => return false,
+        }
+        self.t.next();
+        true
+    }
+
+    fn eat(&mut self, token: &Token<'a>) -> Result<(), ParseError> {
+        match self.t.next() {
+            Some(Ok(ref t)) if token == t => Ok(()),
+            Some(Ok(t)) => Err(ParseError::new(
+                self.t.orig,
+                UnexpectedToken {
+                    expected: token.classify(),
+                    found: t.classify(),
+                },
+            )),
+            Some(Err(e)) => Err(e),
+            None => Err(ParseError::new(
+                self.t.orig,
+                IncompleteExpr(token.classify()),
+            )),
+        }
+    }
+
+    /// Returns the rest of the input from the current location.
+    fn rest(&self) -> Option<&str> {
+        let mut s = self.t.s.clone();
+        loop {
+            match s.next() {
+                Some((_, ' ')) => {}
+                Some((start, _ch)) => return Some(&self.t.orig[start..]),
+                None => return None,
+            }
+        }
+    }
+}
+
+impl<'a> Iterator for Tokenizer<'a> {
+    type Item = Result<Token<'a>, ParseError>;
+
+    fn next(&mut self) -> Option<Result<Token<'a>, ParseError>> {
+        loop {
+            match self.s.next() {
+                Some((_, ' ')) => {}
+                Some((_, '(')) => return Some(Ok(Token::LeftParen)),
+                Some((_, ')')) => return Some(Ok(Token::RightParen)),
+                Some((_, ',')) => return Some(Ok(Token::Comma)),
+                Some((_, '=')) => return Some(Ok(Token::Equals)),
+                Some((start, '"')) => {
+                    while let Some((end, ch)) = self.s.next() {
+                        if ch == '"' {
+                            return Some(Ok(Token::String(&self.orig[start + 1..end])));
+                        }
+                    }
+                    return Some(Err(ParseError::new(self.orig, UnterminatedString)));
+                }
+                Some((start, ch)) if is_ident_start(ch) => {
+                    while let Some(&(end, ch)) = self.s.peek() {
+                        if !is_ident_rest(ch) {
+                            return Some(Ok(Token::Ident(&self.orig[start..end])));
+                        } else {
+                            self.s.next();
+                        }
+                    }
+                    return Some(Ok(Token::Ident(&self.orig[start..])));
+                }
+                Some((_, ch)) => {
+                    return Some(Err(ParseError::new(self.orig, UnexpectedChar(ch))));
+                }
+                None => return None,
+            }
+        }
+    }
+}
+
+fn is_ident_start(ch: char) -> bool {
+    ch == '_' || ch.is_ascii_alphabetic()
+}
+
+fn is_ident_rest(ch: char) -> bool {
+    is_ident_start(ch) || ch.is_ascii_digit()
+}
+
+impl<'a> Token<'a> {
+    fn classify(&self) -> &'static str {
+        match *self {
+            Token::LeftParen => "`(`",
+            Token::RightParen => "`)`",
+            Token::Ident(..) => "an identifier",
+            Token::Comma => "`,`",
+            Token::Equals => "`=`",
+            Token::String(..) => "a string",
+        }
+    }
+}
diff --git a/crates/cargo-platform/src/error.rs b/crates/cargo-platform/src/error.rs
new file mode 100644
index 0000000..bf4b35f
--- /dev/null
+++ b/crates/cargo-platform/src/error.rs
@@ -0,0 +1,67 @@
+use std::fmt;
+
+#[derive(Debug)]
+pub struct ParseError {
+    kind: ParseErrorKind,
+    orig: String,
+}
+
+#[non_exhaustive]
+#[derive(Debug)]
+pub enum ParseErrorKind {
+    UnterminatedString,
+    UnexpectedChar(char),
+    UnexpectedToken {
+        expected: &'static str,
+        found: &'static str,
+    },
+    IncompleteExpr(&'static str),
+    UnterminatedExpression(String),
+    InvalidTarget(String),
+}
+
+impl fmt::Display for ParseError {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(
+            f,
+            "failed to parse `{}` as a cfg expression: {}",
+            self.orig, self.kind
+        )
+    }
+}
+
+impl fmt::Display for ParseErrorKind {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        use ParseErrorKind::*;
+        match self {
+            UnterminatedString => write!(f, "unterminated string in cfg"),
+            UnexpectedChar(ch) => write!(
+                f,
+                "unexpected character `{}` in cfg, expected parens, a comma, \
+                 an identifier, or a string",
+                ch
+            ),
+            UnexpectedToken { expected, found } => {
+                write!(f, "expected {}, found {}", expected, found)
+            }
+            IncompleteExpr(expected) => {
+                write!(f, "expected {}, but cfg expression ended", expected)
+            }
+            UnterminatedExpression(s) => {
+                write!(f, "unexpected content `{}` found after cfg expression", s)
+            }
+            InvalidTarget(s) => write!(f, "invalid target specifier: {}", s),
+        }
+    }
+}
+
+impl std::error::Error for ParseError {}
+
+impl ParseError {
+    pub fn new(orig: &str, kind: ParseErrorKind) -> ParseError {
+        ParseError {
+            kind,
+            orig: orig.to_string(),
+        }
+    }
+}
diff --git a/crates/cargo-platform/src/lib.rs b/crates/cargo-platform/src/lib.rs
new file mode 100644
index 0000000..0a3dcf1
--- /dev/null
+++ b/crates/cargo-platform/src/lib.rs
@@ -0,0 +1,146 @@
+//! Platform definition used by Cargo.
+//!
+//! This defines a [`Platform`] type which is used in Cargo to specify a target platform.
+//! There are two kinds, a named target like `x86_64-apple-darwin`, and a "cfg expression"
+//! like `cfg(any(target_os = "macos", target_os = "ios"))`.
+//!
+//! See `examples/matches.rs` for an example of how to match against a `Platform`.
+//!
+//! [`Platform`]: enum.Platform.html
+
+use std::fmt;
+use std::str::FromStr;
+
+mod cfg;
+mod error;
+
+pub use cfg::{Cfg, CfgExpr};
+pub use error::{ParseError, ParseErrorKind};
+
+/// Platform definition.
+#[derive(Eq, PartialEq, Hash, Ord, PartialOrd, Clone, Debug)]
+pub enum Platform {
+    /// A named platform, like `x86_64-apple-darwin`.
+    Name(String),
+    /// A cfg expression, like `cfg(windows)`.
+    Cfg(CfgExpr),
+}
+
+impl Platform {
+    /// Returns whether the Platform matches the given target and cfg.
+    ///
+    /// The named target and cfg values should be obtained from `rustc`.
+    pub fn matches(&self, name: &str, cfg: &[Cfg]) -> bool {
+        match *self {
+            Platform::Name(ref p) => p == name,
+            Platform::Cfg(ref p) => p.matches(cfg),
+        }
+    }
+
+    fn validate_named_platform(name: &str) -> Result<(), ParseError> {
+        if let Some(ch) = name
+            .chars()
+            .find(|&c| !(c.is_alphanumeric() || c == '_' || c == '-' || c == '.'))
+        {
+            if name.chars().any(|c| c == '(') {
+                return Err(ParseError::new(
+                    name,
+                    ParseErrorKind::InvalidTarget(
+                        "unexpected `(` character, cfg expressions must start with `cfg(`"
+                            .to_string(),
+                    ),
+                ));
+            }
+            return Err(ParseError::new(
+                name,
+                ParseErrorKind::InvalidTarget(format!(
+                    "unexpected character {} in target name",
+                    ch
+                )),
+            ));
+        }
+        Ok(())
+    }
+
+    pub fn check_cfg_attributes(&self, warnings: &mut Vec<String>) {
+        fn check_cfg_expr(expr: &CfgExpr, warnings: &mut Vec<String>) {
+            match *expr {
+                CfgExpr::Not(ref e) => check_cfg_expr(e, warnings),
+                CfgExpr::All(ref e) | CfgExpr::Any(ref e) => {
+                    for e in e {
+                        check_cfg_expr(e, warnings);
+                    }
+                }
+                CfgExpr::Value(ref e) => match e {
+                    Cfg::Name(name) => match name.as_str() {
+                        "test" | "debug_assertions" | "proc_macro" =>
+                            warnings.push(format!(
+                                "Found `{}` in `target.'cfg(...)'.dependencies`. \
+                                 This value is not supported for selecting dependencies \
+                                 and will not work as expected. \
+                                 To learn more visit \
+                                 https://doc.rust-lang.org/cargo/reference/specifying-dependencies.html#platform-specific-dependencies",
+                                 name
+                            )),
+                        _ => (),
+                    },
+                    Cfg::KeyPair(name, _) => if name.as_str() == "feature" {
+                        warnings.push(String::from(
+                            "Found `feature = ...` in `target.'cfg(...)'.dependencies`. \
+                             This key is not supported for selecting dependencies \
+                             and will not work as expected. \
+                             Use the [features] section instead: \
+                             https://doc.rust-lang.org/cargo/reference/features.html"
+                        ))
+                    },
+                }
+            }
+        }
+
+        if let Platform::Cfg(cfg) = self {
+            check_cfg_expr(cfg, warnings);
+        }
+    }
+}
+
+impl serde::Serialize for Platform {
+    fn serialize<S>(&self, s: S) -> Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        self.to_string().serialize(s)
+    }
+}
+
+impl<'de> serde::Deserialize<'de> for Platform {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        let s = String::deserialize(deserializer)?;
+        FromStr::from_str(&s).map_err(serde::de::Error::custom)
+    }
+}
+
+impl FromStr for Platform {
+    type Err = ParseError;
+
+    fn from_str(s: &str) -> Result<Platform, ParseError> {
+        if s.starts_with("cfg(") && s.ends_with(')') {
+            let s = &s[4..s.len() - 1];
+            s.parse().map(Platform::Cfg)
+        } else {
+            Platform::validate_named_platform(s)?;
+            Ok(Platform::Name(s.to_string()))
+        }
+    }
+}
+
+impl fmt::Display for Platform {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match *self {
+            Platform::Name(ref n) => n.fmt(f),
+            Platform::Cfg(ref e) => write!(f, "cfg({})", e),
+        }
+    }
+}
diff --git a/crates/cargo-platform/tests/test_cfg.rs b/crates/cargo-platform/tests/test_cfg.rs
new file mode 100644
index 0000000..dd99d9a
--- /dev/null
+++ b/crates/cargo-platform/tests/test_cfg.rs
@@ -0,0 +1,251 @@
+use cargo_platform::{Cfg, CfgExpr, Platform};
+use std::fmt;
+use std::str::FromStr;
+
+macro_rules! c {
+    ($a:ident) => {
+        Cfg::Name(stringify!($a).to_string())
+    };
+    ($a:ident = $e:expr) => {
+        Cfg::KeyPair(stringify!($a).to_string(), $e.to_string())
+    };
+}
+
+macro_rules! e {
+    (any($($t:tt),*)) => (CfgExpr::Any(vec![$(e!($t)),*]));
+    (all($($t:tt),*)) => (CfgExpr::All(vec![$(e!($t)),*]));
+    (not($($t:tt)*)) => (CfgExpr::Not(Box::new(e!($($t)*))));
+    (($($t:tt)*)) => (e!($($t)*));
+    ($($t:tt)*) => (CfgExpr::Value(c!($($t)*)));
+}
+
+fn good<T>(s: &str, expected: T)
+where
+    T: FromStr + PartialEq + fmt::Debug,
+    T::Err: fmt::Display,
+{
+    let c = match T::from_str(s) {
+        Ok(c) => c,
+        Err(e) => panic!("failed to parse `{}`: {}", s, e),
+    };
+    assert_eq!(c, expected);
+}
+
+fn bad<T>(s: &str, err: &str)
+where
+    T: FromStr + fmt::Display,
+    T::Err: fmt::Display,
+{
+    let e = match T::from_str(s) {
+        Ok(cfg) => panic!("expected `{}` to not parse but got {}", s, cfg),
+        Err(e) => e.to_string(),
+    };
+    assert!(
+        e.contains(err),
+        "when parsing `{}`,\n\"{}\" not contained \
+         inside: {}",
+        s,
+        err,
+        e
+    );
+}
+
+#[test]
+fn cfg_syntax() {
+    good("foo", c!(foo));
+    good("_bar", c!(_bar));
+    good(" foo", c!(foo));
+    good(" foo  ", c!(foo));
+    good(" foo  = \"bar\"", c!(foo = "bar"));
+    good("foo=\"\"", c!(foo = ""));
+    good(" foo=\"3\"      ", c!(foo = "3"));
+    good("foo = \"3 e\"", c!(foo = "3 e"));
+}
+
+#[test]
+fn cfg_syntax_bad() {
+    bad::<Cfg>("", "but cfg expression ended");
+    bad::<Cfg>(" ", "but cfg expression ended");
+    bad::<Cfg>("\t", "unexpected character");
+    bad::<Cfg>("7", "unexpected character");
+    bad::<Cfg>("=", "expected identifier");
+    bad::<Cfg>(",", "expected identifier");
+    bad::<Cfg>("(", "expected identifier");
+    bad::<Cfg>("foo (", "unexpected content `(` found after cfg expression");
+    bad::<Cfg>("bar =", "expected a string");
+    bad::<Cfg>("bar = \"", "unterminated string");
+    bad::<Cfg>(
+        "foo, bar",
+        "unexpected content `, bar` found after cfg expression",
+    );
+}
+
+#[test]
+fn cfg_expr() {
+    good("foo", e!(foo));
+    good("_bar", e!(_bar));
+    good(" foo", e!(foo));
+    good(" foo  ", e!(foo));
+    good(" foo  = \"bar\"", e!(foo = "bar"));
+    good("foo=\"\"", e!(foo = ""));
+    good(" foo=\"3\"      ", e!(foo = "3"));
+    good("foo = \"3 e\"", e!(foo = "3 e"));
+
+    good("all()", e!(all()));
+    good("all(a)", e!(all(a)));
+    good("all(a, b)", e!(all(a, b)));
+    good("all(a, )", e!(all(a)));
+    good("not(a = \"b\")", e!(not(a = "b")));
+    good("not(all(a))", e!(not(all(a))));
+}
+
+#[test]
+fn cfg_expr_bad() {
+    bad::<CfgExpr>(" ", "but cfg expression ended");
+    bad::<CfgExpr>(" all", "expected `(`");
+    bad::<CfgExpr>("all(a", "expected `)`");
+    bad::<CfgExpr>("not", "expected `(`");
+    bad::<CfgExpr>("not(a", "expected `)`");
+    bad::<CfgExpr>("a = ", "expected a string");
+    bad::<CfgExpr>("all(not())", "expected identifier");
+    bad::<CfgExpr>(
+        "foo(a)",
+        "unexpected content `(a)` found after cfg expression",
+    );
+}
+
+#[test]
+fn cfg_matches() {
+    assert!(e!(foo).matches(&[c!(bar), c!(foo), c!(baz)]));
+    assert!(e!(any(foo)).matches(&[c!(bar), c!(foo), c!(baz)]));
+    assert!(e!(any(foo, bar)).matches(&[c!(bar)]));
+    assert!(e!(any(foo, bar)).matches(&[c!(foo)]));
+    assert!(e!(all(foo, bar)).matches(&[c!(foo), c!(bar)]));
+    assert!(e!(all(foo, bar)).matches(&[c!(foo), c!(bar)]));
+    assert!(e!(not(foo)).matches(&[c!(bar)]));
+    assert!(e!(not(foo)).matches(&[]));
+    assert!(e!(any((not(foo)), (all(foo, bar)))).matches(&[c!(bar)]));
+    assert!(e!(any((not(foo)), (all(foo, bar)))).matches(&[c!(foo), c!(bar)]));
+
+    assert!(!e!(foo).matches(&[]));
+    assert!(!e!(foo).matches(&[c!(bar)]));
+    assert!(!e!(foo).matches(&[c!(fo)]));
+    assert!(!e!(any(foo)).matches(&[]));
+    assert!(!e!(any(foo)).matches(&[c!(bar)]));
+    assert!(!e!(any(foo)).matches(&[c!(bar), c!(baz)]));
+    assert!(!e!(all(foo)).matches(&[c!(bar), c!(baz)]));
+    assert!(!e!(all(foo, bar)).matches(&[c!(bar)]));
+    assert!(!e!(all(foo, bar)).matches(&[c!(foo)]));
+    assert!(!e!(all(foo, bar)).matches(&[]));
+    assert!(!e!(not(bar)).matches(&[c!(bar)]));
+    assert!(!e!(not(bar)).matches(&[c!(baz), c!(bar)]));
+    assert!(!e!(any((not(foo)), (all(foo, bar)))).matches(&[c!(foo)]));
+}
+
+#[test]
+fn bad_target_name() {
+    bad::<Platform>(
+        "any(cfg(unix), cfg(windows))",
+        "failed to parse `any(cfg(unix), cfg(windows))` as a cfg expression: \
+         invalid target specifier: unexpected `(` character, \
+         cfg expressions must start with `cfg(`",
+    );
+    bad::<Platform>(
+        "!foo",
+        "failed to parse `!foo` as a cfg expression: \
+         invalid target specifier: unexpected character ! in target name",
+    );
+}
+
+#[test]
+fn round_trip_platform() {
+    fn rt(s: &str) {
+        let p = Platform::from_str(s).unwrap();
+        let s2 = p.to_string();
+        let p2 = Platform::from_str(&s2).unwrap();
+        assert_eq!(p, p2);
+    }
+    rt("x86_64-apple-darwin");
+    rt("foo");
+    rt("cfg(windows)");
+    rt("cfg(target_os = \"windows\")");
+    rt(
+        "cfg(any(all(any(target_os = \"android\", target_os = \"linux\"), \
+         any(target_arch = \"aarch64\", target_arch = \"arm\", target_arch = \"powerpc64\", \
+         target_arch = \"x86\", target_arch = \"x86_64\")), \
+         all(target_os = \"freebsd\", target_arch = \"x86_64\")))",
+    );
+}
+
+#[test]
+fn check_cfg_attributes() {
+    fn ok(s: &str) {
+        let p = Platform::Cfg(s.parse().unwrap());
+        let mut warnings = Vec::new();
+        p.check_cfg_attributes(&mut warnings);
+        assert!(
+            warnings.is_empty(),
+            "Expected no warnings but got: {:?}",
+            warnings,
+        );
+    }
+
+    fn warn(s: &str, names: &[&str]) {
+        let p = Platform::Cfg(s.parse().unwrap());
+        let mut warnings = Vec::new();
+        p.check_cfg_attributes(&mut warnings);
+        assert_eq!(
+            warnings.len(),
+            names.len(),
+            "Expecter warnings about {:?} but got {:?}",
+            names,
+            warnings,
+        );
+        for (name, warning) in names.iter().zip(warnings.iter()) {
+            assert!(
+                warning.contains(name),
+                "Expected warning about '{}' but got: {}",
+                name,
+                warning,
+            );
+        }
+    }
+
+    ok("unix");
+    ok("windows");
+    ok("any(not(unix), windows)");
+    ok("foo");
+
+    ok("target_arch = \"abc\"");
+    ok("target_feature = \"abc\"");
+    ok("target_os = \"abc\"");
+    ok("target_family = \"abc\"");
+    ok("target_env = \"abc\"");
+    ok("target_endian = \"abc\"");
+    ok("target_pointer_width = \"abc\"");
+    ok("target_vendor = \"abc\"");
+    ok("bar = \"def\"");
+
+    warn("test", &["test"]);
+    warn("debug_assertions", &["debug_assertions"]);
+    warn("proc_macro", &["proc_macro"]);
+    warn("feature = \"abc\"", &["feature"]);
+
+    warn("any(not(debug_assertions), windows)", &["debug_assertions"]);
+    warn(
+        "any(not(feature = \"def\"), target_arch = \"abc\")",
+        &["feature"],
+    );
+    warn(
+        "any(not(target_os = \"windows\"), proc_macro)",
+        &["proc_macro"],
+    );
+    warn(
+        "any(not(feature = \"windows\"), proc_macro)",
+        &["feature", "proc_macro"],
+    );
+    warn(
+        "all(not(debug_assertions), any(windows, proc_macro))",
+        &["debug_assertions", "proc_macro"],
+    );
+}