Replace "codegen" with "derive"

2026-04-25 11:37:55 +00:00 · 2017-04-14 15:42:27 -07:00
parent 5b118fdef4
commit 6d55501dab
15 changed files with 8 additions and 8 deletions
@@ -0,0 +1,123 @@
+// Copyright 2017 Serde Developers
+//
+// 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 std::ascii::AsciiExt;
+use std::str::FromStr;
+
+use self::RenameRule::*;
+
+#[derive(Debug, PartialEq)]
+pub enum RenameRule {
+    /// Don't apply a default rename rule.
+    None,
+    /// Rename direct children to "PascalCase" style, as typically used for enum variants.
+    PascalCase,
+    /// Rename direct children to "camelCase" style.
+    CamelCase,
+    /// Rename direct children to "snake_case" style, as commonly used for fields.
+    SnakeCase,
+    /// Rename direct children to "SCREAMING_SNAKE_CASE" style, as commonly used for constants.
+    ScreamingSnakeCase,
+    /// Rename direct children to "kebab-case" style.
+    KebabCase,
+}
+
+impl RenameRule {
+    pub fn apply_to_variant(&self, variant: &str) -> String {
+        match *self {
+            None | PascalCase => variant.to_owned(),
+            CamelCase => variant[..1].to_ascii_lowercase() + &variant[1..],
+            SnakeCase => {
+                let mut snake = String::new();
+                for (i, ch) in variant.char_indices() {
+                    if i > 0 && ch.is_uppercase() {
+                        snake.push('_');
+                    }
+                    snake.push(ch.to_ascii_lowercase());
+                }
+                snake
+            }
+            ScreamingSnakeCase => SnakeCase.apply_to_variant(variant).to_ascii_uppercase(),
+            KebabCase => SnakeCase.apply_to_variant(variant).replace('_', "-"),
+        }
+    }
+
+    pub fn apply_to_field(&self, field: &str) -> String {
+        match *self {
+            None | SnakeCase => field.to_owned(),
+            PascalCase => {
+                let mut pascal = String::new();
+                let mut capitalize = true;
+                for ch in field.chars() {
+                    if ch == '_' {
+                        capitalize = true;
+                    } else if capitalize {
+                        pascal.push(ch.to_ascii_uppercase());
+                        capitalize = false;
+                    } else {
+                        pascal.push(ch);
+                    }
+                }
+                pascal
+            }
+            CamelCase => {
+                let pascal = PascalCase.apply_to_field(field);
+                pascal[..1].to_ascii_lowercase() + &pascal[1..]
+            }
+            ScreamingSnakeCase => field.to_ascii_uppercase(),
+            KebabCase => field.replace('_', "-"),
+        }
+    }
+}
+
+impl FromStr for RenameRule {
+    type Err = ();
+
+    fn from_str(rename_all_str: &str) -> Result<Self, Self::Err> {
+        match rename_all_str {
+            "PascalCase" => Ok(PascalCase),
+            "camelCase" => Ok(CamelCase),
+            "snake_case" => Ok(SnakeCase),
+            "SCREAMING_SNAKE_CASE" => Ok(ScreamingSnakeCase),
+            "kebab-case" => Ok(KebabCase),
+            _ => Err(()),
+        }
+    }
+}
+
+#[test]
+fn rename_variants() {
+    for &(original, camel, snake, screaming, kebab) in
+        &[("Outcome", "outcome", "outcome", "OUTCOME", "outcome"),
+          ("VeryTasty", "veryTasty", "very_tasty", "VERY_TASTY", "very-tasty"),
+          ("A", "a", "a", "A", "a"),
+          ("Z42", "z42", "z42", "Z42", "z42")] {
+        assert_eq!(None.apply_to_variant(original), original);
+        assert_eq!(PascalCase.apply_to_variant(original), original);
+        assert_eq!(CamelCase.apply_to_variant(original), camel);
+        assert_eq!(SnakeCase.apply_to_variant(original), snake);
+        assert_eq!(ScreamingSnakeCase.apply_to_variant(original), screaming);
+        assert_eq!(KebabCase.apply_to_variant(original), kebab);
+    }
+}
+
+#[test]
+fn rename_fields() {
+    for &(original, pascal, camel, screaming, kebab) in
+        &[("outcome", "Outcome", "outcome", "OUTCOME", "outcome"),
+          ("very_tasty", "VeryTasty", "veryTasty", "VERY_TASTY", "very-tasty"),
+          ("a", "A", "a", "A", "a"),
+          ("z42", "Z42", "z42", "Z42", "z42")] {
+        assert_eq!(None.apply_to_field(original), original);
+        assert_eq!(PascalCase.apply_to_field(original), pascal);
+        assert_eq!(CamelCase.apply_to_field(original), camel);
+        assert_eq!(SnakeCase.apply_to_field(original), original);
+        assert_eq!(ScreamingSnakeCase.apply_to_field(original), screaming);
+        assert_eq!(KebabCase.apply_to_field(original), kebab);
+    }
+}