diff --git a/test/ConcurrentCollectionsTests/src/ConcurrentCollectionsTests.jl b/test/ConcurrentCollectionsTests/src/ConcurrentCollectionsTests.jl
index 3d3c532..0df12c5 100644
--- a/test/ConcurrentCollectionsTests/src/ConcurrentCollectionsTests.jl
+++ b/test/ConcurrentCollectionsTests/src/ConcurrentCollectionsTests.jl
@@ -1,5 +1,6 @@
 module ConcurrentCollectionsTests
 
+include("utils.jl")
 include("test_bench_dict_histogram.jl")
 include("test_bench_smoke.jl")
 include("test_crq.jl")
diff --git a/test/ConcurrentCollectionsTests/src/test_crq.jl b/test/ConcurrentCollectionsTests/src/test_crq.jl
index 8eb52ae..edf64f0 100644
--- a/test/ConcurrentCollectionsTests/src/test_crq.jl
+++ b/test/ConcurrentCollectionsTests/src/test_crq.jl
@@ -6,6 +6,7 @@ using ConcurrentCollections.Implementations:
     CRQSlot, IndirectConcurrentRingQueueNode, trypush!, isclosed
 using ProgressLogging: @logprogress, @withprogress
 using Test
+using ..Utils: ⊏
 
 function test_CRQSlot()
     for index in [111, 222],
@@ -16,6 +17,15 @@ function test_CRQSlot()
     end
 end
 
+function test_print_crqslot()
+    slot = CRQSlot(; index = 111, safe = false, storage = UInt32(0xaaa))
+    str = sprint(show, "text/plain", slot)
+    @test "CRQSlot" ⊏ str
+    @test r"index *= *111" ⊏ str
+    @test r"safe *= *false" ⊏ str
+    @test r"storage *= *0x0+aaa" ⊏ str
+end
+
 function unfair_sleep(seconds::Real)
     t0 = time_ns()
     ns = seconds * 1e9
@@ -163,4 +173,10 @@ function check_concurrent_push_pop()
     @test allreceived == 1:nitems
 end
 
+function test_print()
+    crq = IndirectConcurrentRingQueueNode{Int16}(32)
+    str = sprint(show, "text/plain", crq)
+    @test "CRQ: " ⊏ str
+end
+
 end  # module
diff --git a/test/ConcurrentCollectionsTests/src/test_dict.jl b/test/ConcurrentCollectionsTests/src/test_dict.jl
index 6efc695..4b65182 100644
--- a/test/ConcurrentCollectionsTests/src/test_dict.jl
+++ b/test/ConcurrentCollectionsTests/src/test_dict.jl
@@ -4,6 +4,7 @@ using ConcurrentCollections
 using ConcurrentCollections.Implementations: clusters, migrate!
 using SyncBarriers: Barrier, cycle!
 using Test
+using ..Utils: ⊏
 
 function test_expand_and_shrink(n = 17)
     d = ConcurrentDict{Int,Int}()
@@ -259,4 +260,12 @@ function test_phased_push_pop(; nkeys = 16, phases = 2^10, kwargs...)
     @test actual == desired
 end
 
+function test_print()
+    d = ConcurrentDict(111 => 222, 333 => 444)
+    str = sprint(show, "text/plain", d)
+    @test "ConcurrentDict" ⊏ str
+    @test "111 => 222" ⊏ str
+    @test "333 => 444" ⊏ str
+end
+
 end  # module
diff --git a/test/ConcurrentCollectionsTests/src/test_dlcrq.jl b/test/ConcurrentCollectionsTests/src/test_dlcrq.jl
index e20d2c0..e8a1f2d 100644
--- a/test/ConcurrentCollectionsTests/src/test_dlcrq.jl
+++ b/test/ConcurrentCollectionsTests/src/test_dlcrq.jl
@@ -6,6 +6,7 @@ using ConcurrentCollections.Implementations:
     MPCRQSlot, DATA, ANTIDATA, denqueue!, MPCRQ_ENQUEUED
 using ProgressLogging: @logprogress, @withprogress
 using Test
+using ..Utils: ⊏
 
 function test_MPCRQSlot()
     for index in [111, 222],
@@ -169,4 +170,12 @@ function check_concurrent_push_pop!(q; nitems = 2^20)
     @test allreceived == 1:nitems
 end
 
+function test_print()
+    q = DualLinkedConcurrentRingQueue{Int}()
+    push!(q, 333)
+    str = sprint(show, "text/plain", q)
+    @test "Dual LCRQ: " ⊏ str
+    @test "1 data item" ⊏ str
+end
+
 end  # module
diff --git a/test/ConcurrentCollectionsTests/src/test_lcrq.jl b/test/ConcurrentCollectionsTests/src/test_lcrq.jl
index b34ff5c..a31416a 100644
--- a/test/ConcurrentCollectionsTests/src/test_lcrq.jl
+++ b/test/ConcurrentCollectionsTests/src/test_lcrq.jl
@@ -4,6 +4,7 @@ using Base.Experimental: @sync
 using ConcurrentCollections
 using ProgressLogging: @logprogress, @withprogress
 using Test
+using ..Utils: ⊏
 
 function test_push_pop_once_int()
     q = LinkedConcurrentRingQueue{Int}()
@@ -104,4 +105,12 @@ function check_concurrent_push_pop()
     @test allreceived == 1:nitems
 end
 
+function test_print()
+    q = LinkedConcurrentRingQueue{Int}()
+    push!(q, 333)
+    str = sprint(show, "text/plain", q)
+    @test "LCRQ: " ⊏ str
+    @test "1 item" ⊏ str
+end
+
 end  # module
diff --git a/test/ConcurrentCollectionsTests/src/test_mpcrq.jl b/test/ConcurrentCollectionsTests/src/test_mpcrq.jl
index 27adcc0..727a917 100644
--- a/test/ConcurrentCollectionsTests/src/test_mpcrq.jl
+++ b/test/ConcurrentCollectionsTests/src/test_mpcrq.jl
@@ -11,6 +11,7 @@ using ConcurrentCollections.Implementations:
     tryput!
 using ProgressLogging: @logprogress, @withprogress
 using Test
+using ..Utils: ⊏
 
 function test_close()
     crq = IndirectMultiPolarityConcurrentRingQueueNode{Int}(3)
@@ -168,4 +169,10 @@ function check_concurrent_push_pop()
     @test allreceived == 1:nitems
 end
 
+function test_print()
+    crq = IndirectMultiPolarityConcurrentRingQueueNode{Int}(3)
+    str = sprint(show, "text/plain", crq)
+    @test "MP-CRQ: " ⊏ str
+end
+
 end  # module
diff --git a/test/ConcurrentCollectionsTests/src/test_ssqueue.jl b/test/ConcurrentCollectionsTests/src/test_ssqueue.jl
index b35e344..12bd294 100644
--- a/test/ConcurrentCollectionsTests/src/test_ssqueue.jl
+++ b/test/ConcurrentCollectionsTests/src/test_ssqueue.jl
@@ -1,10 +1,11 @@
 module TestSSQueue
 
 using ConcurrentCollections
-using ConcurrentCollections.Implementations: NodeIterator, SSQNode, check_invariance
+using ConcurrentCollections.Implementations: NodeIterator, SSQNode, check_invariance, ==′
 using ProgressLogging: @logprogress, @withprogress
 using Test
 using ..TestDLCRQ: check_concurrent_push_pop!
+using ..Utils: ⊏
 
 function test_push_pop_once_int()
     q = DualLinkedQueue{Int}()
@@ -45,6 +46,14 @@ function test_concurrent_push_pop(ntrials = 100)
     end
 end
 
+function test_iter()
+    q = DualLinkedQueue{Int}()
+    @test eltype(q) === Int
+    push!(q, 111)
+    push!(q, 222)
+    @test collect(q) ==′ [111, 222]
+end
+
 function test_nodeiterator()
     q = DualLinkedQueue{Int}()
     push!(q, 111)
@@ -57,4 +66,12 @@ function test_nodeiterator()
     @test check_invariance(q)
 end
 
+function test_print()
+    q = DualLinkedQueue{Int}()
+    push!(q, 111)
+    push!(q, 222)
+    str = sprint(show, "text/plain", q)
+    @test "DualLinkedQueue" ⊏ str
+end
+
 end  # module
diff --git a/test/ConcurrentCollectionsTests/src/utils.jl b/test/ConcurrentCollectionsTests/src/utils.jl
new file mode 100644
index 0000000..506760b
--- /dev/null
+++ b/test/ConcurrentCollectionsTests/src/utils.jl
@@ -0,0 +1,3 @@
+module Utils
+const ⊏ = occursin
+end  # module