type_convert ignores leading whitespace when imputing column type, and also imputes before trimming

[markpurver]

When converting to character to numeric with imputed column types (col_types=NULL), type_convert ignores leading whitespace when parsing (regardless of whether trim_ws is TRUE or FALSE). It trims trailing whitespace after parsing if trim_ws is TRUE. The argument description says that both leading and trailing whitespace should be trimmed before parsing if trim_ws is TRUE, and implies that neither should be ignored when parsing if trim_ws is FALSE.

# This gives columns of "1" and 2, rather than 1 and 2
type_convert(data.frame(a="1 ", b=" 2"), trim_ws=TRUE)
# This gives columns "1 " and 2, rather than "1 " and " 2"
type_convert(data.frame(a="1 ", b=" 2"), trim_ws=FALSE)