WIP: allow to switch between regex and regex-lite

README.md

@@ -278,15 +278,17 @@ The `ListErrorBuilder::push` and `ListErrorBuilder::insert` methods will ignore
 |--------------------------|-----------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------|
 | `derive`                 | Enables the usage of the `derive(Validate)` macro                                                                                 | [`garde_derive`](https://crates.io/crates/garde_derive)                                      |
 | `url`                    | Validation of URLs via the `url` crate.                                                                                           | [`url`](https://crates.io/crates/url)                                                        |
-| `email`                  | Validation of emails according to [HTML5](https://html.spec.whatwg.org/multipage/forms.html#valid-e-mail-address)                 | [`regex`](https://crates.io/crates/regex), [`once_cell`](https://crates.io/crates/once_cell) |
+| `email`                  | Validation of emails according to [HTML5](https://html.spec.whatwg.org/multipage/forms.html#valid-e-mail-address)                 | [`regex`](https://crates.io/crates/regex) or [`regex-lite`](https://crates.io/crates/regex-lite), [`once_cell`](https://crates.io/crates/once_cell) |
 | `email-idna`             | Support for [Internationalizing Domain Names for Applications](https://url.spec.whatwg.org/#idna) in email addresses              | [`idna`](https://crates.io/crates/idna)                                                      |
-| `pattern`                | Validation using regular expressions via the `regex` crate                                                                        | [`regex`](https://crates.io/crates/regex), [`once_cell`](https://crates.io/crates/once_cell) |
+| `pattern`                | Validation using regular expressions via the `regex` crate                                                                        | [`regex`](https://crates.io/crates/regex) or [`regex-lite`](https://crates.io/crates/regex-lite), [`once_cell`](https://crates.io/crates/once_cell) |
 | `credit-card`            | Validation of credit card numbers via the `card-validate` crate                                                                   | [`card-validate`](https://crates.io/crates/card-validate)                                    |
 | `phone-number`           | Validation of phone numbers via the `phonenumber` crate                                                                           | [`phonenumber`](https://crates.io/crates/phonenumber)                                        |
-| `regex-lite`             | Adds support for the `regex-lite` crate for the pattern validator and switches the email validator to use `regex-lite` instead of `regex` | [`regex-lite`](https://crates.io/crates/regex-lite)                                          |
+| `regex-full`             | Use the `regex` crate in the pattern and email validator  | [`regex`](https://crates.io/crates/regex)                                          |
+| `regex-lite`             | Use the `regex-lite` crate in the pattern and email validator | [`regex-lite`](https://crates.io/crates/regex-lite)                                          |
 
 Additional notes:
-- Enabling the `regex-lite` feature does not remove the dependency on the `regex` crate, but if you avoid using `#[garde(pattern(...)]` with a string literal, then `regex` will not be used and may be removed by link-time optimisation.
+- If you enable the `email` or `pattern` feature, you must also enable either `regex-full` or `regex-lite`.
+- If both `regex-full` and `regex-lite` are enabled, then the `regex-lite` support will be built, but the email validator and the pattern with a string literal will use the `regex` crate, not `regex-lite`.
 
 ### Why `garde`?
 

garde/Cargo.toml

@@ -20,16 +20,19 @@ default = [
     "email",
     "email-idna",
     "pattern",
+    "regex-full",
 ]
 serde = ["dep:serde"]
 derive = ["dep:garde_derive"]
 url = ["dep:url"]
 credit-card = ["dep:card-validate"]
 phone-number = ["dep:phonenumber"]
-email = ["dep:regex", "dep:once_cell"]
+# Requires regex-full or regex-lite.
+email = ["dep:once_cell"]
 email-idna = ["dep:idna"]
-pattern = ["dep:regex", "dep:once_cell", "garde_derive?/regex"]
-regex-lite = ["dep:regex-lite"]
+pattern = ["dep:once_cell"]
+regex-full = ["dep:regex", "garde_derive?/regex-full"]
+regex-lite = ["dep:regex-lite", "garde_derive?/regex-lite"]
 
 [dependencies]
 garde_derive = { version = "0.13.0", path = "../garde_derive", optional = true, default-features = false }

garde/build.rs

@@ -0,0 +1,18 @@
+fn main() {
+    #[cfg(all(
+        feature = "email",
+        not(feature = "regex-full"),
+        not(feature = "regex-lite")
+    ))]
+    panic!("regex-full or regex-lite feature must be enabled when email feature is enabled");
+
+    #[cfg(all(
+        feature = "pattern",
+        not(feature = "regex-full"),
+        not(feature = "regex-lite")
+    ))]
+    panic!("regex-full or regex-lite feature must be enabled when pattern feature is enabled");
+
+    #[cfg(all(feature = "regex-full", feature = "regex-lite"))]
+    println!("cargo:warning=garde: both regex-full and regex-lite features are enabled, using the regex crate in email and pattern validators");
+}

garde/src/lib.rs

@@ -276,12 +276,17 @@
 //! |--------------------------|-----------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------|
 //! | `derive`                 | Enables the usage of the `derive(Validate)` macro                                                                                 | [`garde_derive`](https://crates.io/crates/garde_derive)                                      |
 //! | `url`                    | Validation of URLs via the `url` crate.                                                                                           | [`url`](https://crates.io/crates/url)                                                        |
-//! | `email`                  | Validation of emails according to [HTML5](https://html.spec.whatwg.org/multipage/forms.html#valid-e-mail-address)                 | [`regex`](https://crates.io/crates/regex), [`once_cell`](https://crates.io/crates/once_cell) |
+//! | `email`                  | Validation of emails according to [HTML5](https://html.spec.whatwg.org/multipage/forms.html#valid-e-mail-address)                 | [`regex`](https://crates.io/crates/regex) or [`regex-lite`](https://crates.io/crates/regex-lite), [`once_cell`](https://crates.io/crates/once_cell) |
 //! | `email-idna`             | Support for [Internationalizing Domain Names for Applications](https://url.spec.whatwg.org/#idna) in email addresses              | [`idna`](https://crates.io/crates/idna)                                                      |
-//! | `pattern`                | Validation using regular expressions via the `regex` crate                                                                        | [`regex`](https://crates.io/crates/regex), [`once_cell`](https://crates.io/crates/once_cell) |
+//! | `pattern`                | Validation using regular expressions via the `regex` crate                                                                        | [`regex`](https://crates.io/crates/regex) or [`regex-lite`](https://crates.io/crates/regex-lite), [`once_cell`](https://crates.io/crates/once_cell) |
 //! | `credit-card`            | Validation of credit card numbers via the `card-validate` crate                                                                   | [`card-validate`](https://crates.io/crates/card-validate)                                    |
 //! | `phone-number`           | Validation of phone numbers via the `phonenumber` crate                                                                           | [`phonenumber`](https://crates.io/crates/phonenumber)                                        |
-//! | `regex-lite`             | Adds support for the `regex-lite` crate for the pattern validator and switches the email validator to use `regex-lite` instead of `regex` | [`regex-lite`](https://crates.io/crates/regex-lite)                                          |
+//! | `regex-full`             | Use the `regex` crate in the pattern and email validator  | [`regex`](https://crates.io/crates/regex)                                          |
+//! | `regex-lite`             | Use the `regex-lite` crate in the pattern and email validator | [`regex-lite`](https://crates.io/crates/regex-lite)                                          |
+//!
+//! Additional notes:
+//! - If you enable the `email` or `pattern` feature, you must also enable either `regex-full` or `regex-lite`.
+//! - If both `regex-full` and `regex-lite` are enabled, then the `regex-lite` support will be built, but the email validator and the pattern with a string literal will use the `regex` crate, not `regex-lite`.
 
 pub mod error;
 pub mod rules;

garde/src/rules/pattern.rs

@@ -1,6 +1,6 @@
 //! Pattern validation.
 //!
-//! The pattern argument can be a regular expression provided as a string literal, which is then parsed by the [`regex`] crate.
+//! The pattern argument can be a regular expression provided as a string literal, which is then parsed by the [`regex`] (if the `regex-full` feature is enabled) or [`regex_lite`] crate (if _only_ the `regex-lite` feature is enabled).
 //!
 //! ```rust
 //! #[derive(garde::Validate)]
@@ -11,7 +11,7 @@
 //! ```
 //!
 //! Alternatively, it can be an expression of type implementing [`IsMatch`] or one that dereferences to a [`IsMatch`].
-//! [`IsMatch`] is implemented for `regex::Regex`, `regex_lite::Regex` (if `regex-lite` feature is enabled) and `once_cell::sync::Lazy<T>` with any `T: IsMatch`.
+//! [`IsMatch`] is implemented for `regex::Regex` (if the `regex-full` feature is enabled), `regex_lite::Regex` (if the `regex-lite` feature is enabled) and `once_cell::sync::Lazy<T>` with any `T: IsMatch`.
 //! Please note that the expression will be evaluated each time `validate` is called, so avoid doing any expensive work in the expression.
 //! If the work is unavoidable, at least try to amortize it, such as by using `once_cell::Lazy` or the nightly-only `std::sync::LazyLock`.
 //!
@@ -32,8 +32,12 @@
 //!
 //! This trait has a blanket implementation for all `T: garde::rules::AsStr`.
 
+#[cfg(feature = "regex-full")]
 #[doc(hidden)]
 pub use regex::Regex;
+#[cfg(all(feature = "regex-lite", not(feature = "regex-full")))]
+#[doc(hidden)]
+pub use regex_lite::Regex;
 
 use super::AsStr;
 use crate::error::Error;
@@ -53,7 +57,8 @@ pub trait IsMatch: AsStr {
     fn is_match(&self, haystack: &str) -> bool;
 }
 
-impl IsMatch for Regex {
+#[cfg(feature = "regex-full")]
+impl IsMatch for regex::Regex {
     fn is_match(&self, haystack: &str) -> bool {
         self.is_match(haystack)
     }
@@ -72,7 +77,8 @@ impl<T: IsMatch> IsMatch for once_cell::sync::Lazy<T> {
     }
 }
 
-impl AsStr for Regex {
+#[cfg(feature = "regex-full")]
+impl AsStr for regex::Regex {
     fn as_str(&self) -> &str {
         self.as_str()
     }

garde/tests/rules/mod.rs

@@ -13,6 +13,7 @@ mod ip;
 mod length;
 mod multi_rule;
 mod option;
+#[cfg(any(feature = "regex-full", feature = "regex-lite"))]
 mod pattern;
 mod phone_number;
 mod prefix;

garde/tests/rules/pattern.rs

@@ -1,16 +1,15 @@
 use once_cell::sync::Lazy;
+
+#[cfg(feature = "regex-full")]
 use regex::Regex;
+#[cfg(not(feature = "regex-full"))]
+use regex_lite::Regex;
 
 use super::util;
 
 mod sub {
     use super::*;
 
-    #[cfg(feature = "regex-lite")]
-    pub static LAZY_RE: Lazy<regex_lite::Regex> =
-        Lazy::new(|| regex_lite::Regex::new(r"^abcd|efgh$").unwrap());
-
-    #[cfg(not(feature = "regex-lite"))]
     pub static LAZY_RE: Lazy<Regex> = Lazy::new(|| Regex::new(r"^abcd|efgh$").unwrap());
 }
 

garde_derive/Cargo.toml

@@ -13,10 +13,13 @@ readme = "../README.md"
 proc-macro = true
 
 [features]
-default = ["regex"]
+default = ["regex-full"]
+regex-full = ["dep:regex"]
+regex-lite = ["dep:regex-lite"]
 
 [dependencies]
 syn = { version = "2", features = ["full"] }
 quote = { version = "1" }
 proc-macro2 = { version = "1" }
 regex = { version = "1", default-features = false, features = ["std"], optional = true }
+regex-lite = { version = "0.1", optional = true }

garde_derive/src/check.rs

@@ -373,10 +373,14 @@ fn check_range_not_ord<T>(range: model::Range<T>) -> syn::Result<model::Validate
 fn check_regex(value: model::Pattern) -> syn::Result<model::ValidatePattern> {
     match value {
         model::Pattern::Lit(lit) => {
-            #[cfg(feature = "regex")]
+            #[cfg(feature = "regex-full")]
             if let Err(e) = regex::Regex::new(&lit.value) {
                 return Err(syn::Error::new(lit.span, format!("invalid regex: {e}")));
             }
+            #[cfg(all(feature = "regex-lite", not(feature = "regex-full")))]
+            if let Err(e) = regex_lite::Regex::new(&lit.value) {
+                return Err(syn::Error::new(lit.span, format!("invalid regex: {e}")));
+            }
             Ok(model::ValidatePattern::Lit(lit.value))
         }
         model::Pattern::Expr(expr) => Ok(model::ValidatePattern::Expr(expr)),