first_line_number/1 returns the first logical line number of the specified Section.

last_line_number/1 returns the last logical line number of the specified Section.

line/2 returns a String containing the contents of logical line number lno which is expected to be within the range the Section represents.

Examples

iex> alias LogicalFile.Section
iex> section = Section.new("test/support/main.source")
iex> assert "%(include.source)" = Section.line(section, 6)

line_matching/2 takes a Section and either a predicate function or a regular expression and returns a tuple {logical_line_no, line} representing the first line from the Section that matches.

Examples

iex> alias LogicalFile.Section
iex> section = Section.new("test/support/main.source")
iex> include = ~r/%((?<file>.*))/
iex> assert {6, "%(include.source)"} = Section.line_matching(section, fn line -> String.length(line) > 5 end)
iex> assert {6, "%(include.source)"} = Section.line_matching(section, include)

lines_matching/2 takes a Section and either a predicate function or a regular expression and returns a list of tuples of the form {logical_lno, line} for each line that matches.

Examples

iex> alias LogicalFile.Section
iex> section = Section.new("test/support/commented.source")
iex> assert [{3, "%% nothing here"}, {6, "%% or here"}] = Section.lines_matching(section, fn line ->
...>  String.starts_with?(line, "%%")
...> end)
iex> assert [{1, "one"}, {2, "two"}, {8, "six"}] = Section.lines_matching(section, fn line -> String.length(line) <4 end)

new/1 creates a new Section representing lines from the specified file.

new/4 creates a new Section representing the contents of the file specified by source_path and representing a particular range of logical line numbers and their offset new/4 for more information.

a range of lines with an offset. he offset determines how the line numbers in the range are converted into lines in the source file. For example if the offset is -5 then line 10 will correspond to line 5 of the source file.

Examples

iex> alias LogicalFile.Section
iex> section = Section.new("test/support/main.source")
iex> assert "test/support/main.source" = section.source_path
iex> assert 11 = Section.size(section)
iex> assert 1..11 = section.range
iex> assert 0 = section.offset

iex> alias LogicalFile.Section
iex> %Section{source_path: source_path, range: range, lines: lines} =
...>  Section.new("foo.source", 1..6, ["one", "two", "three", "four", "five", "six"])
iex> assert "foo.source" = source_path
iex> assert 1..6 = range
iex> assert 6 = Enum.count(lines)

iex> alias LogicalFile.Section
iex> %Section{offset: offset} = Section.new("foo.source", 1..2, ["one", "two"], -7)
iex> assert -7 = offset

iex> alias LogicalFile.Section
iex> assert_raise(RuntimeError, fn ->
...> %Section{} =
...>  Section.new("foo.source", 1..5, ["one", "two", "three", "four"])
...> end)

resolve_line/2 takes a Section and a logical line number line that is expected to be within the range of the Section and returns a tuple {file, line} representing the file backing the Section and the corresponding local line number within the Section

number Maps a line number coming from a source map that may include many sections into a line number relative to the section. For example a section may represent source included from another file.

E.g. File 1 contains 20 lines & File 2 contains 10 lines if we insert File 2 we get a structure like:

Lines 1..10 => File 1: Lines 1..10 Lines 11..20 => File 2: Lines 1..10 Lines 21..30 => File 1: Lines 11..20

If we ask for line 15 this maps to File 2, line 5. This means file 2 is offset from the map by -10. If we ask for line 25 this maps to file 1 line 15, again offset by -10.

Examples

iex> alias LogicalFile.Section
iex> section =
...>  Section.new("test/support/main.source")
...>  |> Section.set_range(21..30)
...>  |> Section.set_offset(-10)
iex> assert {"test/support/main.source", 15} = Section.resolve_line(section, 25)

set_offset/2 replaces the line number offset of the specified Section.

set_range/2 replaces the logical line number range of the specified Section.

shift/2 takes a Section and a number of lines to offset the section by_lines and returns a new Section containing the same lines with the logical line number range and offset shifted appropriately.

Examples

iex> alias LogicalFile.Section
iex> section =
...>  Section.new("foo.source", 1..4, ["one", "two", "three", "four"])
...>  |> Section.shift(10)
iex> assert 11..14 = section.range
iex> assert -10 = section.offset

size/1 returns the number of lines in the specified Section.

Examples

iex> alias LogicalFile.Section
iex> section = Section.new("foo.source", 1..4, ["one", "two", "three", "four"])
iex> assert 4 = Section.size(section)

split/2 takes a Section and a logical line number at_line expected to be within the Section and returns a tuple {before_section, after_section} derived by splitting the contents of the Section at the specified line.

The before_section contains all lines up to, but not including, the specified line, the after_section contains all lines from the specified line to the end of the Section.

Note: It is illegal to attempt to split a Section containing one line, or to set the split point on the first or last line of a Section. In any of these cases an exception is raised.

Examples

iex> alias LogicalFile.Section
iex> section = Section.new("foo.source", 1..6, ["one", "two", "three", "four", "five", "six"])
iex> {%Section{} = first, %Section{} = second} = Section.split(section, 4)
iex> assert "foo.source" = first.source_path
iex> assert 1..3 = first.range
iex> assert ["one", "two", "three"] = first.lines
iex> assert "foo.source" = second.source_path
iex> assert 4..6 = second.range
iex> assert ["four", "five", "six"] = second.lines

iex> alias LogicalFile.Section
iex> assert_raise(RuntimeError, fn ->
...>  section = Section.new("foo.source", 1..4, ["one", "two", "three", "four"])
...>  Section.split(section, 0)
...> end)

iex> alias LogicalFile.Section
iex> section = Section.new("foo.source", 1..3, ["alpha", "beta", "delta"]) |> Section.shift(36)
iex> {s1, s2} = Section.split(section, 38)
iex> assert %Section{range: 37..37, offset: -36, lines: ["alpha"]} = s1
iex> assert %Section{range: 38..39, offset: -36, lines: ["beta", "delta"]} = s2

iex> alias LogicalFile.Section
iex> section = Section.new("bar.source", 29..33, ["         ", "   ", "", "end", ""], -4)
iex> {s1, s2} = Section.split(section, 30)
iex> assert %Section{range: 29..29, offset: -4, lines: ["         "]} = s1
iex> assert %Section{range: 30..33, offset: -4, lines: ["   ", "", "end", ""]} = s2

splittable?/1 takes a Section and determines whether it is splittable. In general it's not splittable if it contains only one line.

Examples

iex> alias LogicalFile.Section
iex> section1 = Section.new("bar.source", 1..1, ["one"])
iex> section2 = Section.new("foo.source", 1..2, ["one", "two"])
iex> assert not Section.splittable?(section1)
iex> assert Section.splittable?(section2)

total_size/1 returns the number of lines contained in the given list of Sections.

Examples

iex> alias LogicalFile.Section
iex> section1 = Section.new("foo.source", 1..4, ["one", "two", "three", "four"])
iex> section2 = Section.new("bar.source", 5..7, ["alpha", "beta", "delta"])
iex> assert 7 = Section.total_size([section1, section2])

update_line/3 takes a Section a logical number number expected to be within the Section and a function. It replaces that line with the result of calling the function with the existing line.

Examples

iex> alias LogicalFile.Section
iex> section = Section.new("test/support/main.source")
...>  |> Section.update_line(6, fn line -> String.duplicate(" ", String.length(line)) end)
iex> assert "                 " = Section.line(section, 6)