Refactor config parsing files

This is a large refactor of the config parsing structure, attempting to
reduce the size of the file a bit by splitting it up into different
modules with more specific purposes.

This also fixes #2279.

1 files changed, 81 insertions, 0 deletions

diff --git a/alacritty_terminal/src/config/scrolling.rs b/alacritty_terminal/src/config/scrolling.rs
new file mode 100644
index 00000000..d62b102f
--- /dev/null
+++ b/alacritty_terminal/src/config/scrolling.rs
@@ -0,0 +1,81 @@
+use serde::{Deserialize, Deserializer};
+
+use crate::config::{failure_default, MAX_SCROLLBACK_LINES};
+
+/// Struct for scrolling related settings
+#[serde(default)]
+#[derive(Deserialize, Copy, Clone, Default, Debug, PartialEq, Eq)]
+pub struct Scrolling {
+    #[serde(deserialize_with = "failure_default")]
+    history: ScrollingHistory,
+    #[serde(deserialize_with = "failure_default")]
+    multiplier: ScrollingMultiplier,
+    #[serde(deserialize_with = "failure_default")]
+    faux_multiplier: ScrollingMultiplier,
+    #[serde(deserialize_with = "failure_default")]
+    pub auto_scroll: bool,
+}
+
+impl Scrolling {
+    pub fn history(self) -> u32 {
+        self.history.0
+    }
+
+    pub fn multiplier(self) -> u8 {
+        self.multiplier.0
+    }
+
+    pub fn faux_multiplier(self) -> u8 {
+        self.faux_multiplier.0
+    }
+
+    // Update the history size, used in ref tests
+    pub fn set_history(&mut self, history: u32) {
+        self.history = ScrollingHistory(history);
+    }
+}
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Deserialize)]
+struct ScrollingMultiplier(u8);
+
+impl Default for ScrollingMultiplier {
+    fn default() -> Self {
+        ScrollingMultiplier(3)
+    }
+}
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+struct ScrollingHistory(u32);
+
+impl Default for ScrollingHistory {
+    fn default() -> Self {
+        ScrollingHistory(10_000)
+    }
+}
+
+impl<'de> Deserialize<'de> for ScrollingHistory {
+    fn deserialize<D>(deserializer: D) -> ::std::result::Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        let value = serde_yaml::Value::deserialize(deserializer)?;
+        match u32::deserialize(value) {
+            Ok(lines) => {
+                if lines > MAX_SCROLLBACK_LINES {
+                    error!(
+                        "Problem with config: scrollback size is {}, but expected a maximum of \
+                         {}; using {1} instead",
+                        lines, MAX_SCROLLBACK_LINES,
+                    );
+                    Ok(ScrollingHistory(MAX_SCROLLBACK_LINES))
+                } else {
+                    Ok(ScrollingHistory(lines))
+                }
+            },
+            Err(err) => {
+                error!("Problem with config: {}; using default value", err);
+                Ok(Default::default())
+            },
+        }
+    }
+}