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> ## tests of boundary cases in read.table()
> # empty file
> file.create("foo1")
[1] TRUE
> try(read.table("foo1")) # fails
Error in read.table("foo1") : no lines available in input
> read.table("foo1", col.names=LETTERS[1:4])
[1] A B C D
<0 rows> (or 0-length row.names)
> unlink("foo1")
> 
> # header only
> cat("head\n", file = "foo2")
> read.table("foo2")
    V1
1 head
> try(read.table("foo2", header=TRUE)) # fails in 1.2.3
[1] head
<0 rows> (or 0-length row.names)
> unlink("foo2")
> # header detection
> cat("head\n", 1:2, "\n", 3:4, "\n", file = "foo3")
> read.table("foo3", header=TRUE)
  head
1    2
3    4
> read.table("foo3", header=TRUE, col.names="V1")
  V1
1  2
3  4
> read.table("foo3", header=TRUE, row.names=1)
  head
1    2
3    4
> read.table("foo3", header=TRUE, row.names="row.names")
  head
1    2
3    4
> read.table("foo3", header=TRUE, row.names="head") # fails in 1.2.3
  row.names
2         1
4         3
> 
> # wrong col.names
> try(read.table("foo3", header=TRUE, col.names=letters[1:4]))
Error in scan(file = file, what = what, sep = sep, quote = quote, skip = 0,  : 
    line 1 did not have 4 elements
In addition: Warning message: 
header and `col.names' are of different lengths in: read.table("foo3", header = TRUE, col.names = letters[1:4]) 
> unlink("foo3")
> 
> # incomplete last line
> cat("head\n", 1:2, "\n", 3:4, file = "foo4")
> read.table("foo4", header=TRUE)
  head
1    2
3    4
Warning message: 
incomplete final line in: readLines(con, n, ok) 
> unlink("foo4")
> 
> # blank last line
> cat("head\n\n", 1:2, "\n", 3:4, "\n\n", file = "foo5")
> read.table("foo5", header=TRUE)
  head
1    2
3    4
> 
> # test of fill
> read.table("foo5", header=FALSE, fill=TRUE, blank.lines.skip=FALSE) # fails in 1.2.3
    V1 V2
1 head NA
2      NA
3    1  2
4    3  4
5      NA
> unlink("foo5")
> 
> cat("head\n", 1:2, "\n", 3:5, "\n", 6:9, "\n", file = "foo6")
> try(read.table("foo6", header=TRUE))
Error in read.table("foo6", header = TRUE) : 
    more columns than column names
> try(read.table("foo6", header=TRUE, fill=TRUE))
Error in read.table("foo6", header = TRUE, fill = TRUE) : 
    more columns than column names
> read.table("foo6", header=FALSE, fill=TRUE)
    V1 V2 V3 V4
1 head NA NA NA
2    1  2 NA NA
3    3  4  5 NA
4    6  7  8  9
> unlink("foo6")
> 
> ## end of tests
>