History, more test coverage improvements, and refactorings. (#3217)

Improvements overall to Nu. Also among the changes here, we can also be more confident towards incorporating `3041`. End to end tests for checking envs properly exported to externals is not added here (since it's in the other PR)

A few things added in this PR (probably forgetting some too)

* no writes happen to history during test runs.
* environment syncing end to end coverage added.
* clean up / refactorings few areas.
* testing API for finer control (can write tests passing more than one pipeline)
* can pass environment variables in tests that nu will inherit when running.

* No longer needed.

* no longer under a module. No need to use super.

crates/nu-data/src/config.rs

@@ -1,5 +1,6 @@
 mod conf;
 mod nuconfig;
+pub mod path;
 
 pub mod tests;
 
@@ -185,7 +186,7 @@ pub fn default_path_for(file: &Option<PathBuf>) -> Result<PathBuf, ShellError> {
     let file: &Path = file
         .as_ref()
         .map(AsRef::as_ref)
-        .unwrap_or_else(|| "config.toml".as_ref());
+        .unwrap_or_else(|| self::path::DEFAULT_CONFIG_LOCATION.as_ref());
     filename.push(file);
 
     Ok(filename)

crates/nu-data/src/config/conf.rs

@@ -1,7 +1,9 @@
 use nu_protocol::Value;
+use std::any::Any;
 use std::fmt::Debug;
 
 pub trait Conf: Debug + Send {
+    fn as_any(&self) -> &dyn Any;
     fn is_modified(&self) -> Result<bool, Box<dyn std::error::Error>>;
     fn var(&self, key: &str) -> Option<Value>;
     fn env(&self) -> Option<Value>;
@@ -11,6 +13,10 @@ pub trait Conf: Debug + Send {
 }
 
 impl Conf for Box<dyn Conf> {
+    fn as_any(&self) -> &dyn Any {
+        self
+    }
+
     fn is_modified(&self) -> Result<bool, Box<dyn std::error::Error>> {
         (**self).is_modified()
     }

crates/nu-data/src/config/nuconfig.rs

@@ -2,15 +2,22 @@ use crate::config::{last_modified, read, Conf, Status};
 use indexmap::IndexMap;
 use nu_protocol::Value;
 use nu_source::Tag;
+use std::any::Any;
 use std::fmt::Debug;
+use std::path::PathBuf;
 
 #[derive(Debug, Clone, Default)]
 pub struct NuConfig {
+    pub source_file: Option<std::path::PathBuf>,
     pub vars: IndexMap<String, Value>,
     pub modified_at: Status,
 }
 
 impl Conf for NuConfig {
+    fn as_any(&self) -> &dyn Any {
+        self
+    }
+
     fn is_modified(&self) -> Result<bool, Box<dyn std::error::Error>> {
         self.is_modified()
     }
@@ -30,7 +37,7 @@ impl Conf for NuConfig {
     fn reload(&mut self) {
         let vars = &mut self.vars;
 
-        if let Ok(variables) = read(Tag::unknown(), &None) {
+        if let Ok(variables) = read(Tag::unknown(), &self.source_file) {
             vars.extend(variables);
 
             self.modified_at = if let Ok(status) = last_modified(&None) {
@@ -60,6 +67,7 @@ impl NuConfig {
                 };
 
                 NuConfig {
+                    source_file: source_file.clone(),
                     vars,
                     modified_at: NuConfig::get_last_modified(&source_file),
                 }
@@ -75,11 +83,16 @@ impl NuConfig {
         };
 
         NuConfig {
+            source_file: None,
             vars,
             modified_at: NuConfig::get_last_modified(&None),
         }
     }
 
+    pub fn history_path(&self) -> PathBuf {
+        super::path::history(self)
+    }
+
     pub fn get_last_modified(config_file: &Option<std::path::PathBuf>) -> Status {
         if let Ok(status) = last_modified(config_file) {
             status
@@ -91,15 +104,17 @@ impl NuConfig {
     pub fn is_modified(&self) -> Result<bool, Box<dyn std::error::Error>> {
         let modified_at = &self.modified_at;
 
-        Ok(match (NuConfig::get_last_modified(&None), modified_at) {
-            (Status::LastModified(left), Status::LastModified(right)) => {
-                let left = left.duration_since(std::time::UNIX_EPOCH)?;
-                let right = (*right).duration_since(std::time::UNIX_EPOCH)?;
+        Ok(
+            match (NuConfig::get_last_modified(&self.source_file), modified_at) {
+                (Status::LastModified(left), Status::LastModified(right)) => {
+                    let left = left.duration_since(std::time::UNIX_EPOCH)?;
+                    let right = (*right).duration_since(std::time::UNIX_EPOCH)?;
 
-                left != right
-            }
-            (_, _) => false,
-        })
+                    left != right
+                }
+                (_, _) => false,
+            },
+        )
     }
 
     pub fn var(&self, key: &str) -> Option<Value> {

crates/nu-data/src/config/path.rs

@@ -0,0 +1,32 @@
+use crate::config::NuConfig;
+use std::path::PathBuf;
+
+pub const DEFAULT_CONFIG_LOCATION: &str = "config.toml";
+const DEFAULT_HISTORY_LOCATION: &str = "history.txt";
+
+pub fn history(config: &NuConfig) -> PathBuf {
+    let default_path = crate::config::user_data()
+        .map(|mut p| {
+            p.push(DEFAULT_HISTORY_LOCATION);
+            p
+        })
+        .unwrap_or_else(|_| PathBuf::from(DEFAULT_HISTORY_LOCATION));
+
+    let path = &config.var("history-path");
+
+    path.as_ref().map_or(default_path.clone(), |custom_path| {
+        match custom_path.as_string() {
+            Ok(path) => PathBuf::from(path),
+            Err(_) => default_path,
+        }
+    })
+}
+
+pub fn source_file(config: &NuConfig) -> PathBuf {
+    match &config.source_file {
+        Some(path) => PathBuf::from(path),
+        None => {
+            crate::config::default_path().unwrap_or_else(|_| PathBuf::from(DEFAULT_CONFIG_LOCATION))
+        }
+    }
+}

crates/nu-data/src/config/tests.rs

@@ -1,5 +1,6 @@
 use crate::config::{Conf, NuConfig, Status};
 use nu_protocol::Value;
+use std::any::Any;
 use std::path::{Path, PathBuf};
 
 #[derive(Debug, Clone)]
@@ -9,6 +10,10 @@ pub struct FakeConfig {
 }
 
 impl Conf for FakeConfig {
+    fn as_any(&self) -> &dyn Any {
+        self
+    }
+
     fn is_modified(&self) -> Result<bool, Box<dyn std::error::Error>> {
         self.is_modified()
     }