only add exe path if not using DSC_RESOURCE_PATH

Author: Steve Lee (POWERSHELL HE/HIM) (from Dev Box)

build.ps1

@@ -222,7 +222,7 @@ if (!$Clippy) {
 
     if (!$found) {
         Write-Host -ForegroundCOlor Yellow "Adding $target to `$env:PATH"
-        $env:PATH += [System.IO.Path]::PathSeparator + $target
+        $env:PATH = $target + [System.IO.Path]::PathSeparator + $env:PATH
     }
 }
 

dsc_lib/src/discovery/command_discovery.rs

@@ -14,7 +14,7 @@ use std::fs::File;
 use std::io::BufReader;
 use std::path::Path;
 use std::time::Duration;
-use tracing::{debug, error, warn};
+use tracing::{debug, error, trace, warn};
 
 pub struct CommandDiscovery {
 }
@@ -54,13 +54,22 @@ impl CommandDiscovery {
         let mut resources: BTreeMap<String, DscResource> = BTreeMap::new();
         let mut adapter_resources: Vec<String> = Vec::new();
         let mut remaining_required_resource_types = required_resource_types.to_owned();
+        let mut using_custom_path = false;
 
         // try DSC_RESOURCE_PATH env var first otherwise use PATH
         let path_env = match env::var_os("DSC_RESOURCE_PATH") {
-            Some(value) => value,
+            Some(value) => {
+                debug!("Using DSC_RESOURCE_PATH: {:?}", value.to_string_lossy());
+                using_custom_path = true;
+                value
+            },
             None => {
+                trace!("DSC_RESOURCE_PATH not set, trying PATH");
                 match env::var_os("PATH") {
-                    Some(value) => value,
+                    Some(value) => {
+                        debug!("Using PATH: {:?}", value.to_string_lossy());
+                        value
+                    }
                     None => {
                         return Err(DscError::Operation("Failed to get PATH environment variable".to_string()));
                     }
@@ -71,9 +80,11 @@ impl CommandDiscovery {
         let mut paths = env::split_paths(&path_env).collect::<Vec<_>>();
 
         // add exe home to start of path
-        if let Some(exe_home) = env::current_exe()?.parent() {
-            debug!("Adding exe home to path: {}", exe_home.to_string_lossy());
-            paths.insert(0, exe_home.to_path_buf());
+        if !using_custom_path {
+            if let Some(exe_home) = env::current_exe()?.parent() {
+                debug!("Adding exe home to path: {}", exe_home.to_string_lossy());
+                paths.insert(0, exe_home.to_path_buf());
+            }
         }
 
         for path in paths {