initial tests for AOF (and small changes to server.tcl to support these)

tests/integration/aof.tcl

@@ -0,0 +1,80 @@
+set defaults [list [list appendonly yes] [list appendfilename appendonly.aof]]
+set server_path [tmpdir server.aof]
+set aof_path "$server_path/appendonly.aof"
+
+proc append_to_aof {str} {
+    upvar fp fp
+    puts -nonewline $fp $str
+}
+
+proc create_aof {code} {
+    upvar fp fp aof_path aof_path
+    set fp [open $aof_path w+]
+    uplevel 1 $code
+    close $fp
+}
+
+proc start_server_aof {overrides code} {
+    upvar defaults defaults srv srv server_path server_path
+    set _defaults $defaults
+    set srv [start_server default.conf [lappend _defaults $overrides]]
+    uplevel 1 $code
+    kill_server $srv
+}
+
+## Test the server doesn't start when the AOF contains an unfinished MULTI
+create_aof {
+    append_to_aof [formatCommand set foo hello]
+    append_to_aof [formatCommand multi]
+    append_to_aof [formatCommand set bar world]
+}
+
+start_server_aof [list dir $server_path] {
+    test {Unfinished MULTI: Server should not have been started} {
+        is_alive $srv
+    } {0}
+
+    test {Unfinished MULTI: Server should have logged an error} {
+        exec cat [dict get $srv stdout] | tail -n1
+    } {*Unexpected end of file reading the append only file*}
+}
+
+## Test that the server exits when the AOF contains a short read
+create_aof {
+    append_to_aof [formatCommand set foo hello]
+    append_to_aof [string range [formatCommand set bar world] 0 end-1]
+}
+
+start_server_aof [list dir $server_path] {
+    test {Short read: Server should not have been started} {
+        is_alive $srv
+    } {0}
+
+    test {Short read: Server should have logged an error} {
+        exec cat [dict get $srv stdout] | tail -n1
+    } {*Bad file format reading the append only file*}
+}
+
+## Test that redis-check-aof indeed sees this AOF is not valid
+test {Short read: Utility should confirm the AOF is not valid} {
+    catch {
+        exec ./redis-check-aof $aof_path
+    } str
+    set _ $str
+} {*not valid*}
+
+test {Short read: Utility should be able to fix the AOF} {
+    exec echo y | ./redis-check-aof --fix $aof_path
+} {*Successfully truncated AOF*}
+
+## Test that the server can be started using the truncated AOF
+start_server_aof [list dir $server_path] {
+    test {Fixed AOF: Server should have been started} {
+        is_alive $srv
+    } {1}
+
+    test {Fixed AOF: Keyspace should contain values that were parsable} {
+        set client [redis [dict get $srv host] [dict get $srv port]]
+        list [$client get foo] [$client get bar]
+    } {hello {}}
+}