Merge pull request #2 from mosckital/1-use-case-diagram

Added use case diagram. (#1)

README.md

@@ -1,2 +1,3 @@
-# vscode_python_mro
-VS Code Extension to show the MRO (Method Resolution Order) of classes.
+# VS Code Extension: Python MRO
+
+A Visual Studio Code Extension to show the MRO (Method Resolution Order) of a Python class in the editor.

umls/use_case.md

@@ -0,0 +1,79 @@
+# Use Cases
+
+The main purpose of this VS Code Extension is to facilitate the inspection of the Method Resolution Order of a Python class.
+All the use cases are conceived around this main purpose.
+
+## List of Use Cases
+
+1. **CodeLens Show**: The user can view the MRO of a Python class by clicking the correspondent tag at the CodeLens section in front of the class definition, which will show the MRO list in the newly-occurred interspersed section.
+2. **CodeLens Jump**: The user can click a class name, other than the inspected one, in the appeared MRO list and jump to the correspondent definition of the clicked class.
+3. **Hover Class**: When the user hovers over a class, append the MRO list of the class to the popped contextual information window.
+4. **Hover Object**: When the user hovers over an instance and the class of the instance can be parsed via type hint, append the MRO list of the class to the popped contextual information window.
+5. **Hover Class Method**: When the user hovers over a class method or a static method of a class and the class delegates the method to one of its parent class, append the parent class, which actually fulfils the method call, to the popped contextual information window.
+6. **Hover Object Method**: When the user hovers over a method of an instance and the class of the instance can be parsed via type hint, append the actual class fulfilling the method call, which may be a parent class of the parsed one, to the popped contextual information window.
+
+## Use Case Diagram
+
+The following diagram illustrates the above use case list.
+
+```plantuml
+@startuml
+actor User
+package "Python MRO Extension" {
+    rectangle "CodeLens" {
+        usecase CLS as \
+        "CodeLens Show
+        ==
+        Show class MRO list in
+        the CodeLens section."
+        usecase CLJ as \
+        "CodeLens Jump
+        ==
+        Jump to class definition
+        by clicking class name
+        in the MRO list."
+    }
+    rectangle "Hover" {
+        usecase HC as \
+        "Hover Class
+        ==
+        Append the class MRO list
+        in the popped window when
+        hovering over a class."
+        usecase HO as \
+        "Hover Object
+        ==
+        Append the class MRO list
+        in the popped window when
+        hovering over an object and
+        if its type can be parsed."
+    }
+    rectangle "Hover Method" {
+        usecase HCM as \
+        "Hover Class Method
+        ==
+        Append the actual class
+        fulfilling the method call
+        in the popped window when
+        hovering over a
+        class method."
+        usecase HOM as \
+        "Hover Object Method
+        ==
+        Append the actual class
+        fulfilling the method call
+        in the popped window
+        when hovering over an
+        object method and if its
+        type can be parsed."
+    }
+}
+left to right direction
+User --> CLS
+User --> CLJ
+User --> HC
+User --> HO
+User --> HCM
+User --> HOM
+@enduml
+```