fix inplace bug in rename

Author: risenW

danfojs/src/core/frame.js

@@ -2021,12 +2021,14 @@ export class DataFrame extends Ndframe {
         if (!utils.__key_in_object(kwargs, "mapper")) {
             throw Error("Please specify a mapper object")
         }
-
+        this.print()
+        console.log(kwargs['axis']);
+        console.log(kwargs['inplace']);
         if (kwargs['axis'] == 1) {
             //columns
             let old_col_names = Object.keys(kwargs['mapper'])
             let new_col_names = Object.values(kwargs['mapper'])
-            let col_names = this.column_names
+            let col_names = [...this.column_names]
 
 
             old_col_names.forEach((cname, i) => {
@@ -2037,13 +2039,19 @@ export class DataFrame extends Ndframe {
                 col_names[idx] = new_col_names[i]
 
             })
+            console.log("Before rename");
+            this.print()
             if (kwargs['inplace']) {
                 this.columns = col_names
                 this.__set_col_property(this, this.col_data, col_names, old_col_names)
+                console.log("after rename inplace");
+                this.print()
             } else {
                 let df = this.copy()
                 df.columns = col_names
-                this.__set_col_property(df, df.col_data, col_names, old_col_names)
+                df.__set_col_property(df, df.col_data, col_names, old_col_names)
+                console.log("after rename not inplace");
+                df.print()
                 return df
             }
         } else {

danfojs/tests/core/frame.js

@@ -1945,6 +1945,18 @@ describe("DataFrame", function () {
             let res = ["a1", "b1", "C", "D"]
             assert.deepEqual(df.columns, res)
 
+        })
+        it("confirms original column name is not modified along axis 1", function () {
+            let data = { "A": [-20, 30, 47.3, -20],
+             "B": [34, -4, 5, 6] ,
+             "C": [20, 20, 30, 30] ,
+             "D": ["a", "b", "c", "c"] }
+
+            let ndframe = new DataFrame(data)
+            let df = ndframe.rename({ mapper: { "A": "a1", "B": "b1" } })
+            let res = ["A", "B", "C", "D"]
+            assert.deepEqual(ndframe.columns, res)
+
         })
         it("Rename columns along axis 1 inplace", function () {
             let data = { "A": [-20, 30, 47.3, -20] ,