Auto merge of rust-lang#12948 - epage:toml-refactor, r=weihanglo

refactor(toml): Simplify code to make schema split easier

### What does this PR try to resolve?

This is a follow up to rust-lang#12911 and is prep for rust-lang#12801.

### How should we test and review this PR?

### Additional information

src/cargo/ops/cargo_package.rs

@@ -3,7 +3,6 @@ use std::fs::{self, File};
 use std::io::prelude::*;
 use std::io::SeekFrom;
 use std::path::{Path, PathBuf};
-use std::rc::Rc;
 use std::sync::Arc;
 use std::task::Poll;
 
@@ -412,16 +411,14 @@ fn build_lock(ws: &Workspace<'_>, orig_pkg: &Package) -> CargoResult<String> {
     let orig_resolve = ops::load_pkg_lockfile(ws)?;
 
     // Convert Package -> TomlManifest -> Manifest -> Package
-    let toml_manifest = Rc::new(
-        orig_pkg
-            .manifest()
-            .original()
-            .prepare_for_publish(ws, orig_pkg.root())?,
-    );
+    let toml_manifest = orig_pkg
+        .manifest()
+        .original()
+        .prepare_for_publish(ws, orig_pkg.root())?;
     let package_root = orig_pkg.root();
     let source_id = orig_pkg.package_id().source_id();
     let (manifest, _nested_paths) =
-        TomlManifest::to_real_manifest(&toml_manifest, false, source_id, package_root, config)?;
+        TomlManifest::to_real_manifest(toml_manifest, false, source_id, package_root, config)?;
     let new_pkg = Package::new(manifest, orig_pkg.manifest_path());
 
     let max_rust_version = new_pkg.rust_version().cloned();

src/cargo/util/command_prelude.rs

@@ -6,9 +6,8 @@ use crate::ops::{CompileFilter, CompileOptions, NewOptions, Packages, VersionCon
 use crate::util::important_paths::find_root_manifest_for_wd;
 use crate::util::interning::InternedString;
 use crate::util::is_rustup;
-use crate::util::restricted_names::is_glob_pattern;
-use crate::util::toml::schema::{StringOrVec, TomlProfile};
-use crate::util::validate_package_name;
+use crate::util::restricted_names;
+use crate::util::toml::schema::StringOrVec;
 use crate::util::{
     print_available_benches, print_available_binaries, print_available_examples,
     print_available_packages, print_available_tests,
@@ -607,7 +606,7 @@ Run `{cmd}` to see possible targets."
                 bail!("profile `doc` is reserved and not allowed to be explicitly specified")
             }
             (_, _, Some(name)) => {
-                TomlProfile::validate_name(name)?;
+                restricted_names::validate_profile_name(name)?;
                 name
             }
         };
@@ -801,7 +800,7 @@ Run `{cmd}` to see possible targets."
     ) -> CargoResult<CompileOptions> {
         let mut compile_opts = self.compile_options(config, mode, workspace, profile_checking)?;
         let spec = self._values_of("package");
-        if spec.iter().any(is_glob_pattern) {
+        if spec.iter().any(restricted_names::is_glob_pattern) {
             anyhow::bail!("Glob patterns on package selection are not supported.")
         }
         compile_opts.spec = Packages::Packages(spec);
@@ -835,7 +834,7 @@ Run `{cmd}` to see possible targets."
             (None, None) => config.default_registry()?.map(RegistryOrIndex::Registry),
             (None, Some(i)) => Some(RegistryOrIndex::Index(i.into_url()?)),
             (Some(r), None) => {
-                validate_package_name(r, "registry name", "")?;
+                restricted_names::validate_package_name(r, "registry name", "")?;
                 Some(RegistryOrIndex::Registry(r.to_string()))
             }
             (Some(_), Some(_)) => {
@@ -850,7 +849,7 @@ Run `{cmd}` to see possible targets."
         match self._value_of("registry").map(|s| s.to_string()) {
             None => config.default_registry(),
             Some(registry) => {
-                validate_package_name(&registry, "registry name", "")?;
+                restricted_names::validate_package_name(&registry, "registry name", "")?;
                 Ok(Some(registry))
             }
         }

src/cargo/util/config/mod.rs

@@ -76,7 +76,6 @@ use crate::sources::CRATES_IO_REGISTRY;
 use crate::util::errors::CargoResult;
 use crate::util::network::http::configure_http_handle;
 use crate::util::network::http::http_handle;
-use crate::util::toml as cargo_toml;
 use crate::util::{internal, CanonicalUrl};
 use crate::util::{try_canonicalize, validate_package_name};
 use crate::util::{Filesystem, IntoUrl, IntoUrlWithBase, Rustc};
@@ -1198,7 +1197,7 @@ impl Config {
         }
         let contents = fs::read_to_string(path)
             .with_context(|| format!("failed to read configuration file `{}`", path.display()))?;
-        let toml = cargo_toml::parse_document(&contents, path, self).with_context(|| {
+        let toml = parse_document(&contents, path, self).with_context(|| {
             format!("could not parse TOML configuration in `{}`", path.display())
         })?;
         let def = match why_load {
@@ -2249,7 +2248,7 @@ pub fn save_credentials(
         )
     })?;
 
-    let mut toml = cargo_toml::parse_document(&contents, file.path(), cfg)?;
+    let mut toml = parse_document(&contents, file.path(), cfg)?;
 
     // Move the old token location to the new one.
     if let Some(token) = toml.remove("token") {
@@ -2716,6 +2715,11 @@ impl EnvConfigValue {
 
 pub type EnvConfig = HashMap<String, EnvConfigValue>;
 
+fn parse_document(toml: &str, _file: &Path, _config: &Config) -> CargoResult<toml::Table> {
+    // At the moment, no compatibility checks are needed.
+    toml.parse().map_err(Into::into)
+}
+
 /// A type to deserialize a list of strings from a toml file.
 ///
 /// Supports deserializing either a whitespace-separated list of arguments in a

src/cargo/util/restricted_names.rs

@@ -120,3 +120,82 @@ pub fn is_windows_reserved_path(path: &Path) -> bool {
 pub fn is_glob_pattern<T: AsRef<str>>(name: T) -> bool {
     name.as_ref().contains(&['*', '?', '[', ']'][..])
 }
+
+/// Validate dir-names and profile names according to RFC 2678.
+pub fn validate_profile_name(name: &str) -> CargoResult<()> {
+    if let Some(ch) = name
+        .chars()
+        .find(|ch| !ch.is_alphanumeric() && *ch != '_' && *ch != '-')
+    {
+        bail!(
+            "invalid character `{}` in profile name `{}`\n\
+                Allowed characters are letters, numbers, underscore, and hyphen.",
+            ch,
+            name
+        );
+    }
+
+    const SEE_DOCS: &str = "See https://doc.rust-lang.org/cargo/reference/profiles.html \
+            for more on configuring profiles.";
+
+    let lower_name = name.to_lowercase();
+    if lower_name == "debug" {
+        bail!(
+            "profile name `{}` is reserved\n\
+                 To configure the default development profile, use the name `dev` \
+                 as in [profile.dev]\n\
+                {}",
+            name,
+            SEE_DOCS
+        );
+    }
+    if lower_name == "build-override" {
+        bail!(
+            "profile name `{}` is reserved\n\
+                 To configure build dependency settings, use [profile.dev.build-override] \
+                 and [profile.release.build-override]\n\
+                 {}",
+            name,
+            SEE_DOCS
+        );
+    }
+
+    // These are some arbitrary reservations. We have no plans to use
+    // these, but it seems safer to reserve a few just in case we want to
+    // add more built-in profiles in the future. We can also uses special
+    // syntax like cargo:foo if needed. But it is unlikely these will ever
+    // be used.
+    if matches!(
+        lower_name.as_str(),
+        "build"
+            | "check"
+            | "clean"
+            | "config"
+            | "fetch"
+            | "fix"
+            | "install"
+            | "metadata"
+            | "package"
+            | "publish"
+            | "report"
+            | "root"
+            | "run"
+            | "rust"
+            | "rustc"
+            | "rustdoc"
+            | "target"
+            | "tmp"
+            | "uninstall"
+    ) || lower_name.starts_with("cargo")
+    {
+        bail!(
+            "profile name `{}` is reserved\n\
+                 Please choose a different name.\n\
+                 {}",
+            name,
+            SEE_DOCS
+        );
+    }
+
+    Ok(())
+}

src/cargo/util/toml/embedded.rs

@@ -8,7 +8,7 @@ const DEFAULT_EDITION: crate::core::features::Edition =
     crate::core::features::Edition::LATEST_STABLE;
 const AUTO_FIELDS: &[&str] = &["autobins", "autoexamples", "autotests", "autobenches"];
 
-pub fn expand_manifest(
+pub(super) fn expand_manifest(
     content: &str,
     path: &std::path::Path,
     config: &Config,
@@ -329,7 +329,7 @@ impl DocFragment {
 }
 
 #[derive(Clone, Copy, PartialEq, Debug)]
-pub enum CommentKind {
+enum CommentKind {
     Line,
     Block,
 }