feat: add support for nested sections

Author: HeitorAugustoLN

Cargo.toml

@@ -40,3 +40,11 @@ case-insensitive = ["unicase"]
 # [[A]]
 # Key=value
 brackets-in-section-names = []
+# Allow parsing of nested sections
+#
+# For example:
+# [Section][Subsection]
+# key=value
+#
+# That appears in KDE Configuration files
+nested-sections = []

src/lib.rs

@@ -44,8 +44,7 @@
 
 use std::{
     borrow::Cow,
-    char,
-    error,
+    char, error,
     fmt::{self, Display},
     fs::{File, OpenOptions},
     io::{self, Read, Seek, SeekFrom, Write},
@@ -300,53 +299,51 @@ impl Default for WriteOption {
     }
 }
 
+#[cfg(all(feature = "case-insensitive", not(feature = "nested-sections")))]
+pub type SectionKey = Option<UniCase<String>>;
+#[cfg(all(feature = "case-insensitive", feature = "nested-sections"))]
+pub type SectionKey = Option<Vec<UniCase<String>>>;
+#[cfg(all(not(feature = "case-insensitive"), not(feature = "nested-sections")))]
+pub type SectionKey = Option<String>;
+#[cfg(all(not(feature = "case-insensitive"), feature = "nested-sections"))]
+pub type SectionKey = Option<Vec<String>>;
+
 cfg_if! {
     if #[cfg(feature = "case-insensitive")] {
-        /// Internal storage of section's key
-        pub type SectionKey = Option<UniCase<String>>;
-        /// Internal storage of property's key
-        pub type PropertyKey = UniCase<String>;
-
-        macro_rules! property_get_key {
-            ($s:expr) => {
-                &UniCase::from($s)
-            };
-        }
-
-        macro_rules! property_insert_key {
-            ($s:expr) => {
-                UniCase::from($s)
-            };
-        }
-
-        macro_rules! section_key {
-            ($s:expr) => {
-                $s.map(|s| UniCase::from(s.into()))
-            };
+        cfg_if! {
+            if #[cfg(feature = "nested-sections")] {
+                macro_rules! section_key {
+                    ($s:expr) => {
+                        $s.map(|s| {
+                            s.split("][")
+                                .map(|part| UniCase::from(part.to_string()))
+                                .collect::<Vec<_>>()
+                        })
+                    };
+                }
+            } else {
+                macro_rules! section_key {
+                    ($s:expr) => {
+                        $s.map(|s| UniCase::from(s.into()))
+                    };
+                }
+            }
         }
-
     } else {
-        /// Internal storage of section's key
-        pub type SectionKey = Option<String>;
-        /// Internal storage of property's key
-        pub type PropertyKey = String;
-
-        macro_rules! property_get_key {
-            ($s:expr) => {
-                $s
-            };
-        }
-
-        macro_rules! property_insert_key {
-            ($s:expr) => {
-                $s
-            };
-        }
-
-        macro_rules! section_key {
-            ($s:expr) => {
-                $s.map(Into::into)
-            };
+        cfg_if! {
+            if #[cfg(feature = "nested-sections")] {
+                macro_rules! section_key {
+                    ($s:expr) => {
+                        $s.map(|s| s.split("][").map(Into::into).collect::<Vec<_>>())
+                    };
+                }
+            } else {
+                macro_rules! section_key {
+                    ($s:expr) => {
+                        $s.map(Into::into)
+                    };
+                }
+            }
         }
     }
 }
@@ -959,12 +956,16 @@ impl Ini {
             }
 
             if let Some(ref section) = *section {
-                write!(
-                    writer,
-                    "[{}]{}",
-                    escape_str(&section[..], opt.escape_policy),
-                    opt.line_separator
-                )?;
+                #[cfg(feature = "nested-sections")]
+                let section_str = {
+                    section
+                        .iter()
+                        .map(|part| format!("[{}]", escape_str(part, opt.escape_policy)))
+                        .collect::<String>()
+                };
+                #[cfg(not(feature = "nested-sections"))]
+                let section_str = format!("[{}]", escape_str(section, opt.escape_policy));
+                write!(writer, "{}{}", section_str, opt.line_separator)?;
             }
             for (k, v) in props.iter() {
                 let k_str = escape_str(k, opt.escape_policy);