Refactor cli module

This allows testing the CLI interface

3 files changed, 113 insertions, 15 deletions

diff --git a/TODO.md b/TODO.md
index 3ddd9f9..2ac0519 100644
--- a/TODO.md
+++ b/TODO.md
@@ -1,17 +1,18 @@
 # TODO
 
 ### chores
-1. Add test for clap app
 2. Add significant cursive TUI test
 3. Refactor layout handling (see TODO on `tui::views::LayoutView::relayout`)
 4. Move to `directories 3.0`; optionally migrate existing macos configs? Not
    many people using this anyway...
-5. Add github action to bump homebrew formula on tag push
 6. Move to github actions ASAP, travis & appveyor are a PITA. See resources below.
 
 
 ### bugs
-1. Shift+TAB should move focus backwards
+[ ] Support lack of persistent configuration:
+   1) If we can't write it, still continue with application defaults, and
+   2) allow passing --config-path=PATH;
+[ ] Shift+TAB should move focus backwards
 
 ### feature ideas
 - Add sort option, e.g. relevance|votes|date
@@ -33,7 +34,6 @@ benefit of incorporating termimad features into a cursive view will not be felt.
 But, this is changing [soon](https://meta.stackexchange.com/q/348746).
 
 ### resources for later
-- [GA - bump homebrew](https://github.com/mislav/bump-homebrew-formula-action)
 - [Github Actions example](https://github.com/extrawurst/gitui)
 - [another GA example](https://github.com/casey/just)
 - [logging example](https://deterministic.space/rust-cli-tips.html)
diff --git a/src/cli.rs b/src/cli.rs
index af13f77..707ed3e 100644
--- a/src/cli.rs
+++ b/src/cli.rs
@@ -1,9 +1,10 @@
-use clap::{App, AppSettings, Arg};
+use clap::{App, AppSettings, Arg, ArgMatches};
 
 use crate::config::Config;
 use crate::error::Result;
 
 // TODO --add-site (in addition to defaults)
+// TODO set_api_key should probably just be a bool, since we have config
 pub struct Opts {
     pub list_sites: bool,
     pub print_config_path: bool,
@@ -13,13 +14,23 @@ pub struct Opts {
     pub config: Config,
 }
 
-// TODO accept FnOnce() -> Result<Config> so I can test this
+/// Get CLI opts and args, with defaults pulled from user configuration
 pub fn get_opts() -> Result<Opts> {
-    let config = Config::new()?;
+    get_opts_with(Config::new, |a| a.get_matches())
+}
+
+/// Get CLI opts, starting with defaults produced from `mk_config` and matching args with
+/// `get_matches`.
+fn get_opts_with<F, G>(mk_config: F, get_matches: G) -> Result<Opts>
+where
+    F: FnOnce() -> Result<Config>,
+    G: for<'a> FnOnce(App<'a, '_>) -> ArgMatches<'a>,
+{
+    let config = mk_config()?;
     let limit = &config.limit.to_string();
     let sites = &config.sites.join(";");
     let engine = &config.search_engine.to_string();
-    let matches = App::new("so")
+    let clapp = App::new("so")
         .setting(AppSettings::ColoredHelp)
         .version(clap::crate_version!())
         .author(clap::crate_authors!())
@@ -104,8 +115,8 @@ pub fn get_opts() -> Result<Opts> {
                 .possible_values(&["duckduckgo", "google", "stackexchange"])
                 .help("Use specified search engine")
                 .next_line_help(true),
-        )
-        .get_matches();
+        );
+    let matches = get_matches(clapp);
     let lucky = match (matches.is_present("lucky"), matches.is_present("no-lucky")) {
         (true, _) => true,
         (_, true) => false,
@@ -139,6 +150,93 @@ pub fn get_opts() -> Result<Opts> {
     })
 }
 
-// TODO how can I test this App given
-// https://users.rust-lang.org/t/help-with-idiomatic-rust-and-ownership-semantics/43880
-// Maybe pass get_opts a closure that produces the Config...?
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::config::SearchEngine;
+
+    fn defaults() -> Config {
+        Config {
+            api_key: Some(String::from("my key")),
+            limit: 64,
+            lucky: false,
+            sites: vec![
+                String::from("some"),
+                String::from("sites"),
+                String::from("yeah"),
+            ],
+            search_engine: SearchEngine::DuckDuckGo,
+        }
+    }
+
+    fn mk_config() -> Result<Config> {
+        Ok(defaults())
+    }
+
+    #[test]
+    fn test_defaults() {
+        let opts = get_opts_with(mk_config, |a| {
+            a.get_matches_from(vec!["so", "how do I exit Vim"])
+        });
+
+        assert_eq!(opts.unwrap().config, defaults());
+    }
+
+    #[test]
+    fn test_overrides() {
+        let opts = get_opts_with(mk_config, |a| {
+            a.get_matches_from(vec!["so", "-s", "english", "how do I exit Vim"])
+        });
+
+        assert_eq!(
+            opts.unwrap().config,
+            Config {
+                sites: vec![String::from("english")],
+                ..defaults()
+            }
+        );
+
+        let opts = get_opts_with(mk_config, |a| {
+            a.get_matches_from(vec!["so", "-l", "5", "--lucky", "how do I exit Vim"])
+        });
+
+        assert_eq!(
+            opts.unwrap().config,
+            Config {
+                limit: 5,
+                lucky: true,
+                ..defaults()
+            }
+        );
+    }
+
+    #[test]
+    fn test_set_api_key() {
+        let opts = get_opts_with(mk_config, |a| {
+            a.get_matches_from(vec!["so", "--set-api-key", "new key"])
+        })
+        .unwrap();
+
+        // Uses key in new config
+        assert_eq!(
+            opts.config,
+            Config {
+                api_key: Some(String::from("new key")),
+                ..defaults()
+            }
+        );
+
+        // Flags it in opts
+        assert_eq!(opts.set_api_key, Some(String::from("new key")));
+    }
+
+    #[test]
+    #[should_panic]
+    fn test_conflicts() {
+        get_opts_with(mk_config, |a| {
+            a.get_matches_from_safe(vec!["so", "--lucky", "--no-lucky"])
+                .unwrap()
+        })
+        .unwrap();
+    }
+}
diff --git a/src/config.rs b/src/config.rs
index 65907ba..d5dfe22 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -8,7 +8,7 @@ use std::path::PathBuf;
 use crate::error::{Error, Result};
 use crate::utils;
 
-#[derive(Deserialize, Serialize, Debug, Clone)]
+#[derive(Deserialize, Serialize, Debug, Clone, PartialEq)]
 #[serde(rename_all = "lowercase")]
 pub enum SearchEngine {
     DuckDuckGo,
@@ -16,7 +16,7 @@ pub enum SearchEngine {
     StackExchange,
 }
 
-#[derive(Deserialize, Serialize, Debug, Clone)]
+#[derive(Deserialize, Serialize, Debug, Clone, PartialEq)]
 #[serde(default)]
 pub struct Config {
     pub api_key: Option<String>,