error when using one dimension for indexing (#2553)

Project.toml

@@ -1,6 +1,6 @@
 name = "DataFrames"
 uuid = "a93c6f00-e57d-5684-b7b6-d8193f3e46c0"
-version = "0.22.0"
+version = "0.22.1"
 
 [deps]
 CategoricalArrays = "324d7699-5711-5eae-9e2f-1d82baa6b597"

src/abstractdataframe/abstractdataframe.jl

@@ -1995,3 +1995,11 @@ function repeat_lengths!(longnew::AbstractVector, shortold::AbstractVector,
         counter += l
     end
 end
+
+# Disallowed operations that are a common mistake
+
+Base.getindex(::AbstractDataFrame, ::Union{Symbol, Integer, AbstractString}) =
+    throw(ArgumentError("syntax df[column] is not supported use df[!, column] instead"))
+
+Base.setindex!(::AbstractDataFrame, ::Any, ::Union{Symbol, Integer, AbstractString}) =
+    throw(ArgumentError("syntax df[column] is not supported use df[!, column] instead"))

test/indexing.jl

@@ -1741,14 +1741,14 @@ end
 @testset "unsupported df[col] and df[col] for getindex, view, and setindex!" begin
     @testset "getindex DataFrame" begin
         df = DataFrame(a=1:3, b=4:6, c=7:9)
-        @test_throws MethodError df[1]
+        @test_throws ArgumentError df[1]
         @test_throws MethodError df[end]
         @test_throws MethodError df[1:2]
         @test_throws MethodError df[r"[ab]"]
         @test_throws MethodError df[Not(3)]
         @test_throws MethodError df[:]
-        @test_throws MethodError df[:a]
-        @test_throws MethodError df["a"]
+        @test_throws ArgumentError df[:a]
+        @test_throws ArgumentError df["a"]
     end
     @testset "view DataFrame" begin
         df = DataFrame(a=1:3, b=4:6, c=7:9)
@@ -1763,10 +1763,10 @@ end
     @testset "getindex SubDataFrame" begin
         df = DataFrame(x=-1:3, a=0:4, b=3:7, c=6:10, d=9:13)
         sdf = view(df, 2:4, 2:4)
-        @test_throws MethodError sdf[1]
+        @test_throws ArgumentError sdf[1]
         @test_throws MethodError sdf[end]
-        @test_throws MethodError sdf["x"]
-        @test_throws MethodError sdf[:x]
+        @test_throws ArgumentError sdf[:x]
+        @test_throws ArgumentError sdf["x"]
         @test_throws MethodError sdf[1:2]
         @test_throws MethodError sdf[r"[ab]"]
         @test_throws MethodError sdf[Not(Not(r"[ab]"))]
@@ -1800,7 +1800,7 @@ end
 
         # Broadcasting assignment of columns
         @test_throws MethodError df[:, 1] = 1
-        @test_throws MethodError df[:x3] = 2
+        @test_throws ArgumentError df[:x3] = 2
 
         # assignment of subtables
         @test_throws MethodError df[1, 1:2] = df[2:2, 2:3]
@@ -1848,4 +1848,14 @@ end
     @test_throws ArgumentError dfv."a" = 1
 end
 
+@testset "disallowed getindex and setindex! methods" begin
+    df = DataFrame(a=1)
+    @test_throws ArgumentError df[:a]
+    @test_throws ArgumentError df[:a] = [2]
+    @test_throws ArgumentError df["a"]
+    @test_throws ArgumentError df["a"] = [2]
+    @test_throws ArgumentError df[1]
+    @test_throws ArgumentError df[1] = [2]
+end
+
 end # module