catch test comments updated

test/replication/catch.result

@@ -29,7 +29,7 @@ while box.space.test == nil do fiber.sleep(0.01) end
 ...
 --# set connection default
 --# stop server replica
--- insert values
+-- insert values on the master while replica os stopped and can't fetch them
 for i=1,100 do s:insert{i, 'this is test message12345'} end
 ---
 ...
@@ -40,7 +40,14 @@ errinj.set("ERRINJ_RELAY", true)
 ...
 --# start server replica
 --# set connection replica
--- try to delete
+-- Check that replica doesn't enter read-write mode
+-- before catching up with the master: to check that we inject
+-- sleep into the master relay_send function and attempt a data
+-- modifying statement in replica while it's still fetching
+-- data from the master.
+-- In next 2 cases we try to delete tuple
+-- during fetching process(local delete, remote delete)
+-- case #1: delete tuple in replica
 box.space.test:len()
 ---
 - 1
@@ -52,7 +59,7 @@ box.space.test:get(1) ~= nil
 ---
 - false
 ...
--- try to delete by net.box
+-- case #2: delete tuple by net.box
 --# set connection default
 --# set variable r_uri to 'replica.listen'
 c = net_box:new(r_uri)

test/replication/catch.test.lua

@@ -17,7 +17,7 @@ while box.space.test == nil do fiber.sleep(0.01) end
 --# set connection default
 --# stop server replica
 
--- insert values
+-- insert values on the master while replica os stopped and can't fetch them
 for i=1,100 do s:insert{i, 'this is test message12345'} end
 
 -- sleep after every tuple
@@ -26,12 +26,19 @@ errinj.set("ERRINJ_RELAY", true)
 --# start server replica
 --# set connection replica
 
--- try to delete
+-- Check that replica doesn't enter read-write mode
+-- before catching up with the master: to check that we inject
+-- sleep into the master relay_send function and attempt a data
+-- modifying statement in replica while it's still fetching
+-- data from the master.
+-- In next 2 cases we try to delete tuple
+-- during fetching process(local delete, remote delete)
+-- case #1: delete tuple in replica
 box.space.test:len()
 d = box.space.test:delete{1}
 box.space.test:get(1) ~= nil
 
--- try to delete by net.box
+-- case #2: delete tuple by net.box
 --# set connection default
 --# set variable r_uri to 'replica.listen'
 c = net_box:new(r_uri)