cannot read own output in --continue mode

[dotysan]

Simple steps to reproduce.

First pass:
n3map --verbose --nsec --query-mode=A --continue=er.n3map er

n3map 0.8.2: starting mapping of er.
looking up nameservers for zone er.
using nameserver: 2a13:27c0:30::72 (er.cctld.authdns.ripe.net.)
using nameserver: 196.200.96.1 (sawanew.noc.net.er.)
using nameserver: 196.200.96.2 (zaranew.noc.net.er.)
checking SOA...
checking DNSKEY...
zone file er.n3map does not exist yet, creating it
starting enumeration in A query mode...
warning: walked into a sub-zone at \x00.com.er. (RRSIG signer for NSEC RR does not match zone)
warning: trying to skip confirmed sub-zone com.er.
warning: walked into a sub-zone at \x00.edu.er. (RRSIG signer for NSEC RR does not match zone)
warning: trying to skip confirmed sub-zone edu.er.
warning: walked into a sub-zone at \x00.gov.er. (RRSIG signer for NSEC RR does not match zone)
warning: trying to skip confirmed sub-zone gov.er.
warning: walked into a sub-zone at \x00.ind.er. (subdomain NS received)
warning: trying to skip confirmed sub-zone ind.er.
warning: walked into a sub-zone at \x00.mil.er. (subdomain NS received)
warning: trying to skip confirmed sub-zone mil.er.
warning: walked into a sub-zone at \x00.net.er. (RRSIG signer for NSEC RR does not match zone)
warning: trying to skip confirmed sub-zone net.er.
warning: walked into a sub-zone at \x00.org.er. (RRSIG signer for NSEC RR does not match zone)
warning: trying to skip confirmed sub-zone org.er.
;; walking er.: records =  13; queries =  17; ....................... q/s = 3 ;;
finished mapping of er. in 0:00:04.571137

Second pass:
n3map --verbose --nsec --query-mode=A --continue=er.n3map er

n3map 0.8.2: starting mapping of er.
looking up nameservers for zone er.
using nameserver: 196.200.96.2 (zaranew.noc.net.er.)
using nameserver: 196.200.96.1 (sawanew.noc.net.er.)
using nameserver: 2a13:27c0:30::72 (er.cctld.authdns.ripe.net.)
checking SOA...
checking DNSKEY...
reading NSEC RRs from er.n3map
n3map: fatal: unable to parse input file: 
er.n3map:6: invalid file format

The bug appears to be caused by the //.com.er. in the first pass output:

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;                                    zone: er.
;                                List of NSEC RRs
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
er.     86400   IN      NSEC    com.er. NS SOA RRSIG NSEC DNSKEY CDS CDNSKEY TYPE65534
com.er. 1800    IN      NSEC    //.com.er.      NS SOA RRSIG NSEC DNSKEY CDS CDNSKEY TYPE65534
com.er. 86400   IN      NSEC    edu.er. NS DS RRSIG NSEC
edu.er. 1800    IN      NSEC    mcet.edu.er.    NS SOA RRSIG NSEC DNSKEY CDS CDNSKEY TYPE65534
edu.er. 86400   IN      NSEC    gov.er. NS DS RRSIG NSEC
gov.er. 10800   IN      NSEC    boe.gov.er.     NS SOA RRSIG NSEC DNSKEY CDS CDNSKEY TYPE65534
gov.er. 86400   IN      NSEC    ind.er. NS DS RRSIG NSEC
ind.er. 86400   IN      NSEC    mil.er. NS RRSIG NSEC
mil.er. 86400   IN      NSEC    net.er. NS RRSIG NSEC
net.er. 86400   IN      NSEC    eritel.net.er.  NS SOA RRSIG NSEC DNSKEY CDS CDNSKEY TYPE65534
net.er. 86400   IN      NSEC    org.er. NS DS RRSIG NSEC
org.er. 1800    IN      NSEC    alirizwan.org.er.       NS SOA RRSIG NSEC DNSKEY CDS CDNSKEY TYPE65534
org.er. 86400   IN      NSEC    er.     NS DS RRSIG NSEC
; number of records = 13

;; statistics
; queries = 17