diff --git a/src/main.rs b/src/main.rs
index 3a41e13..77a93cc 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,20 +1,19 @@
-use anyhow::Result;
-use dialoguer::{theme::ColorfulTheme, Input};
+use anyhow::{anyhow, Result};
 use rnote::{app, process};
 
 mod rnote;
 
-/// Check if variable `EDITOR` is set.
+/// Check if variable `EDITOR` and `XDG_DATA_HOME` are set.
 fn check() -> Result<()> {
     let editor = std::env::var("EDITOR").unwrap_or("".to_owned());
-    if editor.is_empty() {
-        let editor: String = Input::with_theme(&ColorfulTheme::default())
-            .with_prompt("Your text editor")
-            .interact_text()?;
-        std::env::set_var("EDITOR", editor);
+    let data_home = std::env::var("XDG_DATA_HOME").unwrap_or("".to_owned());
+    if editor.is_empty() || data_home.is_empty() {
+        Err(anyhow!(
+            "Please make sure variables EDITOR and XDG_DATA_HOME are set."
+        ))
+    } else {
+        Ok(())
     }
-
-    Ok(())
 }
 
 fn main() -> Result<()> {
@@ -34,3 +33,14 @@ fn main() -> Result<()> {
 
     Ok(())
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    #[ignore]
+    fn check_test() {
+        assert!(check().is_ok());
+    }
+}
diff --git a/src/rnote/notes.rs b/src/rnote/notes.rs
index 448bd4a..b10a01a 100644
--- a/src/rnote/notes.rs
+++ b/src/rnote/notes.rs
@@ -7,12 +7,12 @@ use walkdir::WalkDir;
 
 /// Get the path to the root directory of all notes.
 pub fn get_base_path() -> Result<String> {
-    let home = env::var("HOME")?;
+    let home = env::var("XDG_DATA_HOME")?;
     Ok(format!("{}/.rnote/", home))
 }
 
 /// Get path to a category/date directory.
-fn get_path(category: &str) -> Result<String> {
+fn get_category_path(category: &str) -> Result<String> {
     let base = get_base_path()?;
     let date = Utc::now().format("%Y-%m-%d");
     match category.is_empty() {
@@ -21,6 +21,57 @@ fn get_path(category: &str) -> Result<String> {
     }
 }
 
+/// Get all note paths.
+pub fn get_all_notes() -> Result<Vec<String>> {
+    let path = get_base_path()?;
+    let mut files: Vec<String> = Vec::new();
+    for (_, file) in WalkDir::new(path)
+        .into_iter()
+        .filter_map(|file| file.ok())
+        .enumerate()
+    {
+        if file.metadata()?.is_file() {
+            let p = file.path().to_str().unwrap_or("");
+            if !p.is_empty() {
+                files.push(p.to_owned());
+            }
+        }
+    }
+    if files.is_empty() {
+        Err(anyhow!("No notes found."))
+    } else {
+        Ok(files)
+    }
+}
+
+/// Get all notes in category.
+pub fn get_notes_in_category(category: &str) -> Result<Vec<String>> {
+    let base = get_base_path()?;
+    let path = format!("{}{}", base, category);
+    let mut files: Vec<String> = Vec::new();
+    if std::path::Path::new(&path).exists() {
+        for (_, file) in WalkDir::new(path)
+            .into_iter()
+            .filter_map(|file| file.ok())
+            .enumerate()
+        {
+            if file.metadata()?.is_file() {
+                let p = file.path().to_str().unwrap_or("");
+                if !p.is_empty() {
+                    files.push(p.to_owned());
+                }
+            }
+        }
+        if files.is_empty() {
+            Err(anyhow!("Category is empty."))
+        } else {
+            Ok(files)
+        }
+    } else {
+        Err(anyhow!("Category no found."))
+    }
+}
+
 /// Create directory for a note.
 pub fn create_dir(category: &str) -> Result<()> {
     let base = get_base_path()?;
@@ -45,40 +96,8 @@ pub fn create_dir(category: &str) -> Result<()> {
     Ok(())
 }
 
-/// Create a new note.
-pub fn create(header: &str, category: &str) -> Result<()> {
-    let editor = env::var("EDITOR")?;
-    let file = format!("{}{}.md", get_path(category)?, header);
-    create_dir(category)?;
-    is_duplicate(header, category)?;
-    let mut f = fs::File::create(&file)?;
-    f.set_permissions(fs::Permissions::from_mode(0o600))?;
-    f.write(format!("# {}\n", header).as_bytes())?;
-    Command::new(editor).arg(&file).status()?;
-    Ok(())
-}
-
-/// Check if potentially new note name already exists.
-fn is_duplicate(header: &str, category: &str) -> Result<()> {
-    let file = format!("{}{}.md", get_path(category)?, header);
-    let path = format!("{}", get_path(category)?);
-    for entry in WalkDir::new(path) {
-        let entry = entry?;
-        let p: &str = match entry.path().to_str() {
-            Some(s) => s,
-            None => "",
-        };
-        if p == file {
-            return Err(anyhow!(
-                "Duplicate in the same category/date. Choose another name."
-            ));
-        }
-    }
-    Ok(())
-}
-
 /// Find a path to desired note.
-pub fn find_path(header: &str) -> Result<Option<String>> {
+pub fn get_note_path(header: &str) -> Result<Vec<String>> {
     let mut paths: Vec<String> = Vec::new();
     let base = get_base_path()?;
     let header = format!("{}.md", header);
@@ -99,60 +118,12 @@ pub fn find_path(header: &str) -> Result<Option<String>> {
     if paths.is_empty() {
         Err(anyhow!("Note not found."))
     } else {
-        if paths.len() == 1 {
-            Ok(Some(paths.remove(0)))
-        } else {
-            let selection = Select::with_theme(&ColorfulTheme::default())
-                .with_prompt("Optionally choose a note")
-                .default(0)
-                .items(&paths)
-                .interact_opt()?;
-            match selection {
-                Some(s) => Ok(Some(paths.remove(s))),
-                None => Ok(None),
-            }
-        }
+        Ok(paths)
     }
 }
 
-/// Delete a note.
-pub fn remove(header: &str) -> Result<()> {
-    let path = find_path(header)?;
-    if Confirm::with_theme(&ColorfulTheme::default())
-        .with_prompt(format!("Do you want to delete {}?", header))
-        .interact()?
-        && path.is_some()
-    {
-        println!("Deleting...");
-        fs::remove_file(path.unwrap())?;
-        remove_empty_dirs()?;
-        println!("Successfully deleted.");
-        Ok(())
-    } else {
-        Err(anyhow!("Abort."))
-    }
-}
-
-/// Modify a note.
-pub fn modify(header: &str) -> Result<()> {
-    let editor = env::var("EDITOR")?;
-    let file = find_path(header)?;
-    match file {
-        Some(f) => {
-            Command::new(editor).arg(f).status()?;
-            println!("Edited successfully!");
-            Ok(())
-        }
-        None => {
-            println!("Abort.");
-            Ok(())
-        }
-    }
-}
-
-/// Search all notes that contain a given string.
-pub fn search_by_word(word: &str) -> Result<()> {
-    extern crate fstream;
+/// Find all notes that contain a given string.
+pub fn get_files_by_word(word: &str) -> Result<Vec<String>> {
     let path = get_base_path()?;
     let mut paths: Vec<String> = Vec::new();
     for (_, file) in WalkDir::new(path)
@@ -174,6 +145,103 @@ pub fn search_by_word(word: &str) -> Result<()> {
             }
         }
     }
+    Ok(paths)
+}
+
+/// Create a new note.
+pub fn create(header: &str, category: &str) -> Result<()> {
+    let editor = env::var("EDITOR")?;
+    let file = format!("{}{}.md", get_category_path(category)?, header);
+    create_dir(category)?;
+    is_duplicate(header, category)?;
+    let mut f = fs::File::create(&file)?;
+    f.set_permissions(fs::Permissions::from_mode(0o600))?;
+    f.write(format!("# {}\n", header).as_bytes())?;
+    Command::new(editor).arg(&file).status()?;
+    Ok(())
+}
+
+/// Check if potentially new note name already exists.
+fn is_duplicate(header: &str, category: &str) -> Result<()> {
+    let file = format!("{}{}.md", get_category_path(category)?, header);
+    let path = format!("{}", get_category_path(category)?);
+    for entry in WalkDir::new(path) {
+        let entry = entry?;
+        let p: &str = match entry.path().to_str() {
+            Some(s) => s,
+            None => "",
+        };
+        if p == file {
+            return Err(anyhow!(
+                "Duplicate in the same category/date. Choose another name."
+            ));
+        }
+    }
+    Ok(())
+}
+
+/// Find a path to desired note and prompt to choose one to open.
+pub fn get_note_path_interractive(header: &str) -> Result<Option<String>> {
+    let mut paths: Vec<String> = get_note_path(header)?;
+    if paths.len() == 1 {
+        Ok(Some(paths.remove(0)))
+    } else {
+        let selection = Select::with_theme(&ColorfulTheme::default())
+            .with_prompt("Optionally choose a note")
+            .default(0)
+            .items(&paths)
+            .interact_opt()?;
+        match selection {
+            Some(s) => Ok(Some(paths.remove(s))),
+            None => Ok(None),
+        }
+    }
+}
+
+/// Delete a note.
+pub fn remove_note(path: &str) -> Result<()> {
+    println!("Deleting...");
+    fs::remove_file(path)?;
+    remove_empty_dirs()?;
+    println!("Successfully deleted.");
+    Ok(())
+}
+
+/// Prompt user to delete a note.
+pub fn remove_interractive(header: &str) -> Result<()> {
+    let path = get_note_path_interractive(header)?;
+    if Confirm::with_theme(&ColorfulTheme::default())
+        .with_prompt(format!("Do you want to delete {}?", header))
+        .interact()?
+        && path.is_some()
+    {
+        remove_note(&path.unwrap())?;
+        Ok(())
+    } else {
+        Err(anyhow!("Abort."))
+    }
+}
+
+/// Modify a note.
+pub fn modify(header: &str) -> Result<()> {
+    let editor = env::var("EDITOR")?;
+    let file = get_note_path_interractive(header)?;
+    match file {
+        Some(f) => {
+            Command::new(editor).arg(f).status()?;
+            println!("Edited successfully!");
+            Ok(())
+        }
+        None => {
+            println!("Abort.");
+            Ok(())
+        }
+    }
+}
+
+/// Prompt user to open one of found notes by word.
+pub fn search_by_word(word: &str) -> Result<()> {
+    let mut paths: Vec<String> = get_files_by_word(word)?;
     let selection = Select::with_theme(&ColorfulTheme::default())
         .with_prompt("Optionally choose a note")
         .default(0)
@@ -191,17 +259,7 @@ pub fn search_by_word(word: &str) -> Result<()> {
 
 /// Show all notes.
 pub fn show_all() -> Result<()> {
-    let path = get_base_path()?;
-    let mut files: Vec<String> = Vec::new();
-    for (_, file) in WalkDir::new(path)
-        .into_iter()
-        .filter_map(|file| file.ok())
-        .enumerate()
-    {
-        if file.metadata()?.is_file() {
-            files.push(fs::read_to_string(file.path())?);
-        }
-    }
+    let mut files: Vec<String> = get_all_notes()?;
     let skin = show::make_skin();
     let md = &files.join("---\n");
     show::run_app(skin, md)?;
@@ -210,7 +268,7 @@ pub fn show_all() -> Result<()> {
 
 /// Show one note.
 pub fn show(header: &str) -> Result<()> {
-    let path = find_path(header)?;
+    let path = get_note_path_interractive(header)?;
     match path {
         Some(s) => {
             let skin = show::make_skin();
@@ -224,42 +282,16 @@ pub fn show(header: &str) -> Result<()> {
 
 /// Show all notes in the given category.
 pub fn show_category(category: &str) -> Result<()> {
-    let base = get_base_path()?;
-    let path = format!("{}{}", base, category);
-    let mut files: Vec<String> = Vec::new();
-    if std::path::Path::new(&path).exists() {
-        for (_, file) in WalkDir::new(path)
-            .into_iter()
-            .filter_map(|file| file.ok())
-            .enumerate()
-        {
-            if file.metadata()?.is_file() {
-                files.push(fs::read_to_string(file.path())?);
-            }
-        }
-        let skin = show::make_skin();
-        let md = &files.join("---\n");
-        show::run_app(skin, md)?;
-    }
+    let mut files: Vec<String> = get_notes_in_category(category)?;
+    let skin = show::make_skin();
+    let md = &files.join("---\n");
+    show::run_app(skin, md)?;
     Ok(())
 }
 
-/// List all notes and optionally open one.
-pub fn list_all() -> Result<()> {
-    let path = get_base_path()?;
-    let mut files: Vec<String> = Vec::new();
-    for (_, file) in WalkDir::new(path)
-        .into_iter()
-        .filter_map(|file| file.ok())
-        .enumerate()
-    {
-        if file.metadata()?.is_file() {
-            let p = file.path().to_str().unwrap_or("");
-            if !p.is_empty() {
-                files.push(p.to_owned());
-            }
-        }
-    }
+/// List all notes and prompt to open one.
+pub fn list_all_notes() -> Result<()> {
+    let mut files: Vec<String> = get_all_notes()?;
     let selection = Select::with_theme(&ColorfulTheme::default())
         .with_prompt("Optionally choose a note")
         .default(0)
@@ -276,33 +308,17 @@ pub fn list_all() -> Result<()> {
 
 /// List all notes in the given category and optionally open one.
 pub fn list_category(category: &str) -> Result<()> {
-    let base = get_base_path()?;
-    let path = format!("{}{}", base, category);
-    let mut files: Vec<String> = Vec::new();
-    if std::path::Path::new(&path).exists() {
-        for (_, file) in WalkDir::new(path)
-            .into_iter()
-            .filter_map(|file| file.ok())
-            .enumerate()
-        {
-            if file.metadata()?.is_file() {
-                let p = file.path().to_str().unwrap_or("");
-                if !p.is_empty() {
-                    files.push(p.to_owned());
-                }
-            }
-        }
-        let selection = Select::with_theme(&ColorfulTheme::default())
-            .with_prompt("Optionally choose a note")
-            .default(0)
-            .items(&files)
-            .interact_opt()?;
-        if let Some(selection) = selection {
-            let editor = std::env::var("EDITOR")?;
-            std::process::Command::new(editor)
-                .arg(files.remove(selection))
-                .status()?;
-        }
+    let mut files: Vec<String> = get_notes_in_category(category)?;
+    let selection = Select::with_theme(&ColorfulTheme::default())
+        .with_prompt("Optionally choose a note")
+        .default(0)
+        .items(&files)
+        .interact_opt()?;
+    if let Some(selection) = selection {
+        let editor = std::env::var("EDITOR")?;
+        std::process::Command::new(editor)
+            .arg(files.remove(selection))
+            .status()?;
     }
     Ok(())
 }
@@ -346,3 +362,50 @@ fn remove_empty_dirs() -> Result<()> {
 
     Ok(())
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn get_base_path_test() {
+        assert!(get_base_path().is_ok());
+    }
+
+    #[test]
+    fn find_by_word_test() {
+        assert!(get_files_by_word("test").is_ok());
+    }
+
+    #[test]
+    fn get_note_path_test() {
+        assert!(get_note_path("test").is_ok());
+    }
+
+    #[test]
+    fn get_category_path_create_dir_test() {
+        assert!(create_dir("test").is_ok());
+        assert!(get_category_path("test").is_ok());
+    }
+
+    #[test]
+    fn create_remove_test() {
+        assert!(create("test", "test").is_ok());
+        assert!(remove_note("test").is_ok());
+    }
+
+    #[test]
+    fn remove_empty_dirs_test() {
+        assert!(remove_empty_dirs().is_ok());
+    }
+
+    #[test]
+    fn wipe_date_test() {
+        assert!(wipe_date("1999-10-10").is_ok());
+    }
+
+    #[test]
+    fn get_notes_in_category_test() {
+        assert!(get_notes_in_category("test").is_ok());
+    }
+}
diff --git a/src/rnote/process.rs b/src/rnote/process.rs
index 05b83e1..b9fe746 100644
--- a/src/rnote/process.rs
+++ b/src/rnote/process.rs
@@ -20,7 +20,7 @@ pub fn new(matches: &ArgMatches) -> Result<()> {
 /// Process argument `remove`.
 pub fn remove(matches: &ArgMatches) -> Result<()> {
     match matches.value_of("header") {
-        Some(s) => notes::remove(s)?,
+        Some(s) => notes::remove_interractive(s)?,
         None => match matches.is_present("date") {
             true => {
                 let date: String = Input::with_theme(&ColorfulTheme::default())
@@ -33,7 +33,7 @@ pub fn remove(matches: &ArgMatches) -> Result<()> {
                 let header: String = Input::with_theme(&ColorfulTheme::default())
                     .with_prompt("Name of your note")
                     .interact_text()?;
-                notes::remove(&header)?;
+                notes::remove_interractive(&header)?;
             }
         },
     }
@@ -62,7 +62,7 @@ pub fn list(matches: &ArgMatches) -> Result<()> {
                 .interact_text()?;
             notes::list_category(&s)?;
         }
-        false => notes::list_all()?,
+        false => notes::list_all_notes()?,
     }
     Ok(())
 }
@@ -71,7 +71,7 @@ pub fn list(matches: &ArgMatches) -> Result<()> {
 pub fn search(matches: &ArgMatches) -> Result<()> {
     match matches.value_of("header") {
         Some(s) => {
-            let p = notes::find_path(s)?;
+            let p = notes::get_note_path_interractive(s)?;
             match p {
                 Some(s) => {
                     let editor = std::env::var("EDITOR")?;