Preview Changes Identified by Source Tracking

To see changes between your local project and target org, navigate to the project directory for which you want to see changes. Then run one of the preview commands, which display either the local changes in your project you can deploy to your org, or the org changes that you can retrieve.

In a terminal or command window, navigate to the project directory. In this example, the directory is named MyProject.
1cd /Users/joe/dx-projects/MyProject
To see what’s changed between your project and org, run either the project deploy preview or project retrieve preview command. Include the --target-org flag to specify the username or alias of the scratch org or sandbox that you want to compare with your local project. In this example, the command displays the local changes that can be deployed to the sandbox with the alias DevSandbox.
1sf project deploy preview --target-org DevSandbox
Similarly, this example displays the remote changes in the sandbox that can be retrieved back into the local project.
1sf project retrieve preview --target-org DevSandbox
The project deploy preview command accepts the --metadata, --source-dir, and --manifest flags, which you can use to preview more granular deployments. This example previews a deployment of only ApexClass metadata:
1sf project deploy preview --metadata ApexClass --target-org DevSandbox

This project deploy preview sample output shows that there are local changes to the WidgetClass Apex class and WidgetObject__c custom object that can be deployed to the org.

1sf project deploy preview --target-org DevSandbox
2
3No conflicts found.
4
5No files will be deleted.
6
7Will Deploy [2] files.
8 Type         Fullname        Path                                                                           
9 ──────────── ─────────────── ────────────────────────────────────────────────────────────────────────────── 
10 ApexClass    WidgetClass     force-app/main/default/classes/WidgetClass.cls-meta.xml                        
11 CustomObject WidgetObject__c force-app/main/default/objects/WidgetObject__c/WidgetObject__c.object-meta.xml 
12
13No files were ignored. Update your .forceignore file if you want to ignore certain files.

This project retrieve preview sample output shows that there are remote changes to the GizmoClass Apex class and GizmoObject__c custom object (and its layout) that can be retrieved from the org to the local project. The output also shows that there are no conflicts between the project and org.

1sf project retrieve preview --target-org DevSandbox
2
3No conflicts found.
4
5No files will be deleted.
6
7Will Retrieve [3] files.
8 Type         Fullname                          Path 
9 ──────────── ───────────────────────────────── ──── 
10 Layout       GizmoObject__c-GizmoObject Layout      
11 CustomObject GizmoObject__c                         
12 ApexClass    GizmoClass                             
13
14Ignored [2] files. These files won't retrieve because they're ignored by your .forceignore file.
15 Type    Fullname                            Path 
16 ─────── ─────────────────────────────────── ──── 
17 Profile Admin                                    
18 Profile B2B Reordering Portal Buyer Profile

The preview commands use tables of change information with three columns: Type, Fullname, and Path. Each row represents one change.

Type is the changed component’s metadata type. It describes what the component is, such as an Apex class or a custom object.
Fullname is the API name of the component.
Path is the location of the component in your local project. If it’s blank, the component isn’t present in your local project. When blank, it usually means that a component is present in the org but not in your local project.

If source tracking doesn’t detect any changes, then the preview commands return a statement saying No results found.

1=== Source Status
2No results found

After previewing the changes in the source in your local project and the org, you’re ready to deploy or retrieve and resolve potential conflicts.

Salesforce DX Developer Guide

Preview Changes Identified by Source Tracking