Fix zero-length array concatenation validation (#45383)

(cherry picked from commit 0a55a8e)
JuliaLang · Jun 7, 2022 · d6bbed6 · d6bbed6
1 parent b6e47d4
commit d6bbed6
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Showing 2 changed files with 3 additions and 5 deletions.
diff --git a/base/abstractarray.jl b/base/abstractarray.jl
@@ -2478,7 +2478,7 @@ function _typed_hvncat_shape(::Type{T}, shape::NTuple{N, Tuple}, row_first, as::
     shapelength == lengthas || throw(ArgumentError("number of elements does not match shape; expected $(shapelength), got $lengthas)"))
     # discover dimensions
     nd = max(N, cat_ndims(as[1]))
-    outdims = zeros(Int, nd)
+    outdims = fill(-1, nd)
     currentdims = zeros(Int, nd)
     blockcounts = zeros(Int, nd)
     shapepos = ones(Int, nd)
@@ -2503,7 +2503,7 @@ function _typed_hvncat_shape(::Type{T}, shape::NTuple{N, Tuple}, row_first, as::
 
             isendblock = blockcounts[d] == shapev[d][shapepos[d]]
             if isendblock
-                if outdims[d] == 0
+                if outdims[d] == -1
                     outdims[d] = currentdims[d]
                 elseif outdims[d] != currentdims[d]
                     throw(ArgumentError("argument $i has a mismatched number of elements along axis $ad; \

diff --git a/test/abstractarray.jl b/test/abstractarray.jl
@@ -1465,9 +1465,7 @@ using Base: typed_hvncat
     v1 = zeros(Int, 0, 0, 0)
     for v2 ∈ (1, [1])
         for v3 ∈ (2, [2])
-            # current behavior, not potentially dangerous.
-            # should throw error like above loop
-            @test [v1 ;;; v2 v3] == [v2 v3;;;]
+            @test_throws ArgumentError [v1 ;;; v2 v3]
             @test_throws ArgumentError [v1 ;;; v2]
             @test_throws ArgumentError [v1 v1 ;;; v2 v3]
         end