Add a PromQL lexer (#1506)

Including tests and an example.promql file.

2 files changed, 190 insertions, 0 deletions

diff --git a/pygments/lexers/_mapping.py b/pygments/lexers/_mapping.py
index dad78679..1c346c37 100644
--- a/pygments/lexers/_mapping.py
+++ b/pygments/lexers/_mapping.py
@@ -347,6 +347,7 @@ LEXERS = {
     'PowerShellSessionLexer': ('pygments.lexers.shell', 'PowerShell Session', ('ps1con',), (), ()),
     'PraatLexer': ('pygments.lexers.praat', 'Praat', ('praat',), ('*.praat', '*.proc', '*.psc'), ()),
     'PrologLexer': ('pygments.lexers.prolog', 'Prolog', ('prolog',), ('*.ecl', '*.prolog', '*.pro', '*.pl'), ('text/x-prolog',)),
+    'PromQLLexer': ('pygments.lexers.promql', 'PromQL', ('promql',), ('*.promql',), ()),
     'PropertiesLexer': ('pygments.lexers.configs', 'Properties', ('properties', 'jproperties'), ('*.properties',), ('text/x-java-properties',)),
     'ProtoBufLexer': ('pygments.lexers.dsls', 'Protocol Buffer', ('protobuf', 'proto'), ('*.proto',), ()),
     'PugLexer': ('pygments.lexers.html', 'Pug', ('pug', 'jade'), ('*.pug', '*.jade'), ('text/x-pug', 'text/x-jade')),
diff --git a/pygments/lexers/promql.py b/pygments/lexers/promql.py
new file mode 100644
index 00000000..6359fb09
--- /dev/null
+++ b/pygments/lexers/promql.py
@@ -0,0 +1,189 @@
+# -*- coding: utf-8 -*-
+"""
+    pygments.lexers.promql
+    ~~~~~~~~~~~~~~~~~~~~~~
+
+    Lexer for Prometheus Query Language.
+
+    :copyright: Copyright 2006-2020 by the Pygments team, see AUTHORS.
+    :license: BSD, see LICENSE for details.
+"""
+
+from pygments.lexer import RegexLexer, bygroups, default, words
+from pygments.token import (
+    Comment,
+    Keyword,
+    Name,
+    Number,
+    Operator,
+    Punctuation,
+    String,
+    Whitespace,
+)
+
+__all__ = ["PromQLLexer"]
+
+
+class PromQLLexer(RegexLexer):
+    """
+    For `PromQL <https://prometheus.io/docs/prometheus/latest/querying/basics/>`_ queries.
+
+    For details about the grammar see:
+    https://github.com/prometheus/prometheus/tree/master/promql/parser
+
+    .. versionadded: 2.7
+    """
+
+    name = "PromQL"
+    aliases = ["promql"]
+    filenames = ["*.promql"]
+
+    base_keywords = (
+        words(
+            (
+                "bool",
+                "by",
+                "group_left",
+                "group_right",
+                "ignoring",
+                "offset",
+                "on",
+                "without",
+            ),
+            suffix=r"\b",
+        ),
+        Keyword,
+    )
+
+    aggregator_keywords = (
+        words(
+            (
+                "sum",
+                "min",
+                "max",
+                "avg",
+                "group",
+                "stddev",
+                "stdvar",
+                "count",
+                "count_values",
+                "bottomk",
+                "topk",
+                "quantile",
+            ),
+            suffix=r"\b",
+        ),
+        Keyword,
+    )
+
+    function_keywords = (
+        words(
+            (
+                "abs",
+                "absent",
+                "absent_over_time",
+                "avg_over_time",
+                "ceil",
+                "changes",
+                "clamp_max",
+                "clamp_min",
+                "count_over_time",
+                "day_of_month",
+                "day_of_week",
+                "days_in_month",
+                "delta",
+                "deriv",
+                "exp",
+                "floor",
+                "histogram_quantile",
+                "holt_winters",
+                "hour",
+                "idelta",
+                "increase",
+                "irate",
+                "label_join",
+                "label_replace",
+                "ln",
+                "log10",
+                "log2",
+                "max_over_time",
+                "min_over_time",
+                "minute",
+                "month",
+                "predict_linear",
+                "quantile_over_time",
+                "rate",
+                "resets",
+                "round",
+                "scalar",
+                "sort",
+                "sort_desc",
+                "sqrt",
+                "stddev_over_time",
+                "stdvar_over_time",
+                "sum_over_time",
+                "time",
+                "timestamp",
+                "vector",
+                "year",
+            ),
+            suffix=r"\b",
+        ),
+        Keyword.Reserved,
+    )
+
+    tokens = {
+        "root": [
+            (r"\n", Whitespace),
+            (r"\s+", Whitespace),
+            (r",", Punctuation),
+            # Keywords
+            base_keywords,
+            aggregator_keywords,
+            function_keywords,
+            # Offsets
+            (r"[1-9][0-9]*[s|m|h|d|w|y]", String),
+            # Numbers
+            (r"-?[0-9]+\.[0-9]+", Number.Float),
+            (r"-?[0-9]+", Number.Integer),
+            # Comments
+            (r"#.*?$", Comment.Single),
+            # Operators
+            (r"(\+|\-|\*|\/|\%|\^)", Operator),
+            (r"==|!=|>=|<=|<|>", Operator),
+            (r"and|or|unless", Operator.Word),
+            # Metrics
+            (r"[_a-zA-Z][_a-zA-Z0-9]+", Name.Variable),
+            # Params
+            (r'(["\'])(.*?)(["\'])', bygroups(Punctuation, String, Punctuation)),
+            # Other states
+            (r"\(", Operator, "function"),
+            (r"\)", Operator),
+            (r"{", Punctuation, "labels"),
+            (r"\[", Punctuation, "range"),
+        ],
+        "labels": [
+            (r"}", Punctuation, "#pop"),
+            (r"\n", Whitespace),
+            (r"\s+", Whitespace),
+            (r",", Punctuation),
+            (
+                r'([_a-zA-Z][_a-zA-Z0-9]*?)(\s*?)(=|!=|=~|~!)(\s*?)(")(.*?)(")',
+                bygroups(
+                    Name.Label,
+                    Whitespace,
+                    Operator,
+                    Whitespace,
+                    Punctuation,
+                    String,
+                    Punctuation,
+                ),
+            ),
+        ],
+        "range": [(r"\]", Punctuation, "#pop"), (r"[1-9][0-9]*[s|m|h|d|w|y]", String)],
+        "function": [
+            (r"\)", Operator, "#pop"),
+            (r"\(", Operator, "#push"),
+            default("#pop"),
+        ],
+    }