From 6066c8392cd0e021c8d5b811ced8f3a084ac8f17 Mon Sep 17 00:00:00 2001
From: Muhammad <tjmnkrajyej@gmail.com>
Date: Mon, 30 Oct 2023 00:38:52 +0000
Subject: [PATCH] Add default value for `Config::indent`.

---
 helix-core/src/syntax.rs   | 38 ++++++++++++++++++++++++++++++++------
 helix-view/src/document.rs | 23 ++++++++++-------------
 helix-view/src/editor.rs   |  5 ++---
 3 files changed, 44 insertions(+), 22 deletions(-)

diff --git a/helix-core/src/syntax.rs b/helix-core/src/syntax.rs
index 2a789fbd9553b..4d385ce484ec6 100644
--- a/helix-core/src/syntax.rs
+++ b/helix-core/src/syntax.rs
@@ -63,6 +63,21 @@ where
     })
 }
 
+fn deserialize_tab_width_option<'de, D>(deserializer: D) -> Result<Option<usize>, D::Error>
+where
+    D: serde::Deserializer<'de>,
+{
+    usize::deserialize(deserializer).and_then(|n| {
+        if n > 0 && n <= 16 {
+            Ok(Some(n))
+        } else {
+            Err(serde::de::Error::custom(
+                "tab width must be a value from 1 to 16 inclusive",
+            ))
+        }
+    })
+}
+
 pub fn deserialize_auto_pairs<'de, D>(deserializer: D) -> Result<Option<AutoPairs>, D::Error>
 where
     D: serde::Deserializer<'de>,
@@ -436,18 +451,20 @@ pub struct DebuggerQuirks {
     pub absolute_paths: bool,
 }
 
-#[derive(Debug, PartialEq, Eq, Clone, Serialize, Deserialize)]
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
 #[serde(rename_all = "kebab-case")]
 pub struct IndentationConfiguration {
-    #[serde(deserialize_with = "deserialize_tab_width")]
-    pub tab_width: usize,
-    pub unit: String,
+    #[serde(deserialize_with = "deserialize_tab_width_option")]
+    pub tab_width: Option<usize>,
+    pub unit: Option<String>,
 }
 
 #[derive(Debug, Serialize, Deserialize)]
+#[serde(rename_all = "kebab-case")]
 pub struct LanguageIndentationConfiguration {
-    #[serde(flatten)]
-    pub indent: IndentationConfiguration,
+    #[serde(deserialize_with = "deserialize_tab_width")]
+    pub tab_width: usize,
+    pub unit: String,
     #[serde(default)]
     pub required: bool,
 }
@@ -495,6 +512,15 @@ impl FromStr for AutoPairConfig {
     }
 }
 
+impl Default for IndentationConfiguration {
+    fn default() -> Self {
+        IndentationConfiguration {
+            tab_width: None,
+            unit: None,
+        }
+    }
+}
+
 #[derive(Debug)]
 pub struct TextObjectQuery {
     pub query: Query,
diff --git a/helix-view/src/document.rs b/helix-view/src/document.rs
index 2ea1e48f31a2f..6a49cc1543889 100644
--- a/helix-view/src/document.rs
+++ b/helix-view/src/document.rs
@@ -960,7 +960,7 @@ impl Document {
     /// is likewise auto-detected, and will remain unchanged if no line endings were detected.
     pub fn detect_indent_and_line_ending(&mut self) {
         self.indent_style = auto_detect_indent_style(&self.text).unwrap_or_else(|| {
-            self.indent_config(DEFAULT_INDENT, |config| IndentStyle::from_str(&config.unit))
+            self.indent_config(DEFAULT_INDENT, |config| config.unit.as_ref().map(|unit| IndentStyle::from_str(unit)))
         });
         if let Some(line_ending) = auto_detect_line_ending(&self.text) {
             self.line_ending = line_ending;
@@ -999,18 +999,15 @@ impl Document {
         };
     }
 
-    fn indent_config<T, F: Fn(&IndentationConfiguration) -> T>(&self, default: T, mapper: F) -> T {
-        self.language_config()
-            .and_then(|config| config.indent.as_ref())
-            .filter(|config| config.required)
-            .map(|config| mapper(&config.indent))
-            .or_else(|| self.config.load().indent.as_ref().map(&mapper))
-            .or_else(|| {
-                self.language_config()
-                    .and_then(|config| config.indent.as_ref())
-                    .map(|config| mapper(&config.indent))
-            })
-            .unwrap_or(default)
+    fn indent_config<T, F: Fn(IndentationConfiguration) -> Option<T>>(&self, default: T, mapper: F) -> T {
+        let mut indent = self.config.load().indent.clone();
+
+        if let Some(c) = self.language_config().and_then(|config| config.indent.as_ref()) {
+            indent.tab_width = indent.tab_width.filter(|_| !c.required).or(Some(c.tab_width));
+            indent.unit = indent.unit.filter(|_| !c.required).or(Some(c.unit.clone()));
+        }
+
+        mapper(indent).unwrap_or(default)
     }
 
     /// Reload the document from its path.
diff --git a/helix-view/src/editor.rs b/helix-view/src/editor.rs
index ffcb684731b96..fdf7ff92ae40d 100644
--- a/helix-view/src/editor.rs
+++ b/helix-view/src/editor.rs
@@ -276,8 +276,7 @@ pub struct Config {
     pub rulers: Vec<u16>,
     #[serde(default)]
     pub whitespace: WhitespaceConfig,
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub indent: Option<IndentationConfiguration>,
+    pub indent: IndentationConfiguration,
     /// Persistently display open buffers along the top
     pub bufferline: BufferLine,
     /// Vertical indent width guides.
@@ -835,7 +834,7 @@ impl Default for Config {
             terminal: get_terminal_provider(),
             rulers: Vec::new(),
             whitespace: WhitespaceConfig::default(),
-            indent: None,
+            indent: IndentationConfiguration::default(),
             bufferline: BufferLine::default(),
             indent_guides: IndentGuidesConfig::default(),
             color_modes: false,