Add function docs for pipeline module

lib/absinthe/pipeline.ex

@@ -140,6 +140,11 @@ defmodule Absinthe.Pipeline do
 
  @doc """
  Return the part of a pipeline before a specific phase.
+
+ ## Examples
+
+ iex> Pipeline.before([A, B, C], B)
+ [A]
  """
  @spec before(t, atom) :: t
  def before(pipeline, phase) do
@@ -158,6 +163,11 @@ defmodule Absinthe.Pipeline do
 
  @doc """
  Return the part of a pipeline after (and including) a specific phase.
+
+ ## Examples
+
+ iex> Pipeline.from([A, B, C], B)
+ [B, C]
  """
  @spec from(t, atom) :: t
  def from(pipeline, phase) do
@@ -229,6 +239,11 @@ defmodule Absinthe.Pipeline do
 
  @doc """
  Return the part of a pipeline up to and including a specific phase.
+
+ ## Examples
+
+ iex> Pipeline.upto([A, B, C], B)
+ [A, B]
  """
  @spec upto(t, atom) :: t
  def upto(pipeline, phase) do
@@ -237,24 +252,74 @@ defmodule Absinthe.Pipeline do
  beginning ++ [item]
  end
 
+ @doc """
+ Return the pipeline with the supplied phase removed.
+
+ ## Examples
+
+ iex> Pipeline.without([A, B, C], B)
+ [A, C]
+ """
  @spec without(t, Phase.t()) :: t
  def without(pipeline, phase) do
  pipeline
  |> Enum.filter(&(not match_phase?(phase, &1)))
  end
 
+ @doc """
+ Return the pipeline with the phase/list of phases inserted before
+ the supplied phase.
+
+ ## Examples
+
+ Add one phase before another:
+
+ iex> Pipeline.insert_before([A, C, D], C, B)
+ [A, B, C, D]
+
+ Add list of phase before another:
+
+ iex> Pipeline.insert_before([A, D, E], D, [B, C])
+ [A, B, C, D, E]
+
+ """
  @spec insert_before(t, Phase.t(), phase_config_t | [phase_config_t]) :: t
  def insert_before(pipeline, phase, additional) do
  beginning = before(pipeline, phase)
  beginning ++ List.wrap(additional) ++ (pipeline -- beginning)
  end
 
+ @doc """
+ Return the pipeline with the phase/list of phases inserted after
+ the supplied phase.
+
+ ## Examples
+
+ Add one phase after another:
+
+ iex> Pipeline.insert_after([A, C, D], A, B)
+ [A, B, C, D]
+
+ Add list of phases after another:
+
+ iex> Pipeline.insert_after([A, D, E], A, [B, C])
+ [A, B, C, D, E]
+
+ """
  @spec insert_after(t, Phase.t(), phase_config_t | [phase_config_t]) :: t
  def insert_after(pipeline, phase, additional) do
  beginning = upto(pipeline, phase)
  beginning ++ List.wrap(additional) ++ (pipeline -- beginning)
  end
 
+ @doc """
+ Return the pipeline with the phases matching the regex removed.
+
+ ## Examples
+
+ iex> Pipeline.reject([A, B, C], ~r/A|B/)
+ [C]
+ """
  @spec reject(t, Regex.t() | (Module.t() -> boolean)) :: t
  def reject(pipeline, %Regex{} = pattern) do
  reject(pipeline, fn phase ->