
rule all:
    input:
        "test.a.txt"


rule a:
    output:
        "unused.{sample}.txt"
    log:
        "logs/{sample}.txt"
    shell:
        "echo {wildcards.sample} > {log}; touch {output}"


rule b:
    input:
        "logs/{sample}.txt"
    output:
        "test.{sample}.txt"
    shell:
        "cp {input} {output}"
